Alright, let's solve this math problem step by step. First, we have the number 423. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 409. So, we're going to take the number 423 and add it to itself 409 times.
Step 1: 0 + 423 = 423
Step 2: 423 + 423 = 846
Step 3: 846 + 423 = 1269
Step 4: 1269 + 423 = 1692
Step 5: 1692 + 423 = 2115
Step 6: 2115 + 423 = 2538
Step 7: 2538 + 423 = 2961
Step 8: 2961 + 423 = 3384
Step 9: 3384 + 423 = 3807
Step 10: 3807 + 423 = 4230
Step 11: 4230 + 423 = 4653
Step 12: 4653 + 423 = 5076
Step 13: 5076 + 423 = 5499
Step 14: 5499 + 423 = 5922
Step 15: 5922 + 423 = 6345
Step 16: 6345 + 423 = 6768
Step 17: 6768 + 423 = 7191
Step 18: 7191 + 423 = 7614
Step 19: 7614 + 423 = 8037
Step 20: 8037 + 423 = 8460
Step 21: 8460 + 423 = 8883
Step 22: 8883 + 423 = 9306
Step 23: 9306 + 423 = 9729
Step 24: 9729 + 423 = 10152
Step 25: 10152 + 423 = 10575
Step 26: 10575 + 423 = 10998
Step 27: 10998 + 423 = 11421
Step 28: 11421 + 423 = 11844
Step 29: 11844 + 423 = 12267
Step 30: 12267 + 423 = 12690
Step 31: 12690 + 423 = 13113
Step 32: 13113 + 423 = 13536
Step 33: 13536 + 423 = 13959
Step 34: 13959 + 423 = 14382
Step 35: 14382 + 423 = 14805
Step 36: 14805 + 423 = 15228
Step 37: 15228 + 423 = 15651
Step 38: 15651 + 423 = 16074
Step 39: 16074 + 423 = 16497
Step 40: 16497 + 423 = 16920
Step 41: 16920 + 423 = 17343
Step 42: 17343 + 423 = 17766
Step 43: 17766 + 423 = 18189
Step 44: 18189 + 423 = 18612
Step 45: 18612 + 423 = 19035
Step 46: 19035 + 423 = 19458
Step 47: 19458 + 423 = 19881
Step 48: 19881 + 423 = 20304
Step 49: 20304 + 423 = 20727
Step 50: 20727 + 423 = 21150
Step 51: 21150 + 423 = 21573
Step 52: 21573 + 423 = 21996
Step 53: 21996 + 423 = 22419
Step 54: 22419 + 423 = 22842
Step 55: 22842 + 423 = 23265
Step 56: 23265 + 423 = 23688
Step 57: 23688 + 423 = 24111
Step 58: 24111 + 423 = 24534
Step 59: 24534 + 423 = 24957
Step 60: 24957 + 423 = 25380
Step 61: 25380 + 423 = 25803
Step 62: 25803 + 423 = 26226
Step 63: 26226 + 423 = 26649
Step 64: 26649 + 423 = 27072
Step 65: 27072 + 423 = 27495
Step 66: 27495 + 423 = 27918
Step 67: 27918 + 423 = 28341
Step 68: 28341 + 423 = 28764
Step 69: 28764 + 423 = 29187
Step 70: 29187 + 423 = 29610
Step 71: 29610 + 423 = 30033
Step 72: 30033 + 423 = 30456
Step 73: 30456 + 423 = 30879
Step 74: 30879 + 423 = 31302
Step 75: 31302 + 423 = 31725
Step 76: 31725 + 423 = 32148
Step 77: 32148 + 423 = 32571
Step 78: 32571 + 423 = 32994
Step 79: 32994 + 423 = 33417
Step 80: 33417 + 423 = 33840
Step 81: 33840 + 423 = 34263
Step 82: 34263 + 423 = 34686
Step 83: 34686 + 423 = 35109
Step 84: 35109 + 423 = 35532
Step 85: 35532 + 423 = 35955
Step 86: 35955 + 423 = 36378
Step 87: 36378 + 423 = 36801
Step 88: 36801 + 423 = 37224
Step 89: 37224 + 423 = 37647
Step 90: 37647 + 423 = 38070
Step 91: 38070 + 423 = 38493
Step 92: 38493 + 423 = 38916
Step 93: 38916 + 423 = 39339
Step 94: 39339 + 423 = 39762
Step 95: 39762 + 423 = 40185
Step 96: 40185 + 423 = 40608
Step 97: 40608 + 423 = 41031
Step 98: 41031 + 423 = 41454
Step 99: 41454 + 423 = 41877
Step 100: 41877 + 423 = 42300
Step 101: 42300 + 423 = 42723
Step 102: 42723 + 423 = 43146
Step 103: 43146 + 423 = 43569
Step 104: 43569 + 423 = 43992
Step 105: 43992 + 423 = 44415
Step 106: 44415 + 423 = 44838
Step 107: 44838 + 423 = 45261
Step 108: 45261 + 423 = 45684
Step 109: 45684 + 423 = 46107
Step 110: 46107 + 423 = 46530
Step 111: 46530 + 423 = 46953
Step 112: 46953 + 423 = 47376
Step 113: 47376 + 423 = 47799
Step 114: 47799 + 423 = 48222
Step 115: 48222 + 423 = 48645
Step 116: 48645 + 423 = 49068
Step 117: 49068 + 423 = 49491
Step 118: 49491 + 423 = 49914
Step 119: 49914 + 423 = 50337
Step 120: 50337 + 423 = 50760
Step 121: 50760 + 423 = 51183
Step 122: 51183 + 423 = 51606
Step 123: 51606 + 423 = 52029
Step 124: 52029 + 423 = 52452
Step 125: 52452 + 423 = 52875
Step 126: 52875 + 423 = 53298
Step 127: 53298 + 423 = 53721
Step 128: 53721 + 423 = 54144
Step 129: 54144 + 423 = 54567
Step 130: 54567 + 423 = 54990
Step 131: 54990 + 423 = 55413
Step 132: 55413 + 423 = 55836
Step 133: 55836 + 423 = 56259
Step 134: 56259 + 423 = 56682
Step 135: 56682 + 423 = 57105
Step 136: 57105 + 423 = 57528
Step 137: 57528 + 423 = 57951
Step 138: 57951 + 423 = 58374
Step 139: 58374 + 423 = 58797
Step 140: 58797 + 423 = 59220
Step 141: 59220 + 423 = 59643
Step 142: 59643 + 423 = 60066
Step 143: 60066 + 423 = 60489
Step 144: 60489 + 423 = 60912
Step 145: 60912 + 423 = 61335
Step 146: 61335 + 423 = 61758
Step 147: 61758 + 423 = 62181
Step 148: 62181 + 423 = 62604
Step 149: 62604 + 423 = 63027
Step 150: 63027 + 423 = 63450
Step 151: 63450 + 423 = 63873
Step 152: 63873 + 423 = 64296
Step 153: 64296 + 423 = 64719
Step 154: 64719 + 423 = 65142
Step 155: 65142 + 423 = 65565
Step 156: 65565 + 423 = 65988
Step 157: 65988 + 423 = 66411
Step 158: 66411 + 423 = 66834
Step 159: 66834 + 423 = 67257
Step 160: 67257 + 423 = 67680
Step 161: 67680 + 423 = 68103
Step 162: 68103 + 423 = 68526
Step 163: 68526 + 423 = 68949
Step 164: 68949 + 423 = 69372
Step 165: 69372 + 423 = 69795
Step 166: 69795 + 423 = 70218
Step 167: 70218 + 423 = 70641
Step 168: 70641 + 423 = 71064
Step 169: 71064 + 423 = 71487
Step 170: 71487 + 423 = 71910
Step 171: 71910 + 423 = 72333
Step 172: 72333 + 423 = 72756
Step 173: 72756 + 423 = 73179
Step 174: 73179 + 423 = 73602
Step 175: 73602 + 423 = 74025
Step 176: 74025 + 423 = 74448
Step 177: 74448 + 423 = 74871
Step 178: 74871 + 423 = 75294
Step 179: 75294 + 423 = 75717
Step 180: 75717 + 423 = 76140
Step 181: 76140 + 423 = 76563
Step 182: 76563 + 423 = 76986
Step 183: 76986 + 423 = 77409
Step 184: 77409 + 423 = 77832
Step 185: 77832 + 423 = 78255
Step 186: 78255 + 423 = 78678
Step 187: 78678 + 423 = 79101
Step 188: 79101 + 423 = 79524
Step 189: 79524 + 423 = 79947
Step 190: 79947 + 423 = 80370
Step 191: 80370 + 423 = 80793
Step 192: 80793 + 423 = 81216
Step 193: 81216 + 423 = 81639
Step 194: 81639 + 423 = 82062
Step 195: 82062 + 423 = 82485
Step 196: 82485 + 423 = 82908
Step 197: 82908 + 423 = 83331
Step 198: 83331 + 423 = 83754
Step 199: 83754 + 423 = 84177
Step 200: 84177 + 423 = 84600
Step 201: 84600 + 423 = 85023
Step 202: 85023 + 423 = 85446
Step 203: 85446 + 423 = 85869
Step 204: 85869 + 423 = 86292
Step 205: 86292 + 423 = 86715
Step 206: 86715 + 423 = 87138
Step 207: 87138 + 423 = 87561
Step 208: 87561 + 423 = 87984
Step 209: 87984 + 423 = 88407
Step 210: 88407 + 423 = 88830
Step 211: 88830 + 423 = 89253
Step 212: 89253 + 423 = 89676
Step 213: 89676 + 423 = 90099
Step 214: 90099 + 423 = 90522
Step 215: 90522 + 423 = 90945
Step 216: 90945 + 423 = 91368
Step 217: 91368 + 423 = 91791
Step 218: 91791 + 423 = 92214
Step 219: 92214 + 423 = 92637
Step 220: 92637 + 423 = 93060
Step 221: 93060 + 423 = 93483
Step 222: 93483 + 423 = 93906
Step 223: 93906 + 423 = 94329
Step 224: 94329 + 423 = 94752
Step 225: 94752 + 423 = 95175
Step 226: 95175 + 423 = 95598
Step 227: 95598 + 423 = 96021
Step 228: 96021 + 423 = 96444
Step 229: 96444 + 423 = 96867
Step 230: 96867 + 423 = 97290
Step 231: 97290 + 423 = 97713
Step 232: 97713 + 423 = 98136
Step 233: 98136 + 423 = 98559
Step 234: 98559 + 423 = 98982
Step 235: 98982 + 423 = 99405
Step 236: 99405 + 423 = 99828
Step 237: 99828 + 423 = 100251
Step 238: 100251 + 423 = 100674
Step 239: 100674 + 423 = 101097
Step 240: 101097 + 423 = 101520
Step 241: 101520 + 423 = 101943
Step 242: 101943 + 423 = 102366
Step 243: 102366 + 423 = 102789
Step 244: 102789 + 423 = 103212
Step 245: 103212 + 423 = 103635
Step 246: 103635 + 423 = 104058
Step 247: 104058 + 423 = 104481
Step 248: 104481 + 423 = 104904
Step 249: 104904 + 423 = 105327
Step 250: 105327 + 423 = 105750
Step 251: 105750 + 423 = 106173
Step 252: 106173 + 423 = 106596
Step 253: 106596 + 423 = 107019
Step 254: 107019 + 423 = 107442
Step 255: 107442 + 423 = 107865
Step 256: 107865 + 423 = 108288
Step 257: 108288 + 423 = 108711
Step 258: 108711 + 423 = 109134
Step 259: 109134 + 423 = 109557
Step 260: 109557 + 423 = 109980
Step 261: 109980 + 423 = 110403
Step 262: 110403 + 423 = 110826
Step 263: 110826 + 423 = 111249
Step 264: 111249 + 423 = 111672
Step 265: 111672 + 423 = 112095
Step 266: 112095 + 423 = 112518
Step 267: 112518 + 423 = 112941
Step 268: 112941 + 423 = 113364
Step 269: 113364 + 423 = 113787
Step 270: 113787 + 423 = 114210
Step 271: 114210 + 423 = 114633
Step 272: 114633 + 423 = 115056
Step 273: 115056 + 423 = 115479
Step 274: 115479 + 423 = 115902
Step 275: 115902 + 423 = 116325
Step 276: 116325 + 423 = 116748
Step 277: 116748 + 423 = 117171
Step 278: 117171 + 423 = 117594
Step 279: 117594 + 423 = 118017
Step 280: 118017 + 423 = 118440
Step 281: 118440 + 423 = 118863
Step 282: 118863 + 423 = 119286
Step 283: 119286 + 423 = 119709
Step 284: 119709 + 423 = 120132
Step 285: 120132 + 423 = 120555
Step 286: 120555 + 423 = 120978
Step 287: 120978 + 423 = 121401
Step 288: 121401 + 423 = 121824
Step 289: 121824 + 423 = 122247
Step 290: 122247 + 423 = 122670
Step 291: 122670 + 423 = 123093
Step 292: 123093 + 423 = 123516
Step 293: 123516 + 423 = 123939
Step 294: 123939 + 423 = 124362
Step 295: 124362 + 423 = 124785
Step 296: 124785 + 423 = 125208
Step 297: 125208 + 423 = 125631
Step 298: 125631 + 423 = 126054
Step 299: 126054 + 423 = 126477
Step 300: 126477 + 423 = 126900
Step 301: 126900 + 423 = 127323
Step 302: 127323 + 423 = 127746
Step 303: 127746 + 423 = 128169
Step 304: 128169 + 423 = 128592
Step 305: 128592 + 423 = 129015
Step 306: 129015 + 423 = 129438
Step 307: 129438 + 423 = 129861
Step 308: 129861 + 423 = 130284
Step 309: 130284 + 423 = 130707
Step 310: 130707 + 423 = 131130
Step 311: 131130 + 423 = 131553
Step 312: 131553 + 423 = 131976
Step 313: 131976 + 423 = 132399
Step 314: 132399 + 423 = 132822
Step 315: 132822 + 423 = 133245
Step 316: 133245 + 423 = 133668
Step 317: 133668 + 423 = 134091
Step 318: 134091 + 423 = 134514
Step 319: 134514 + 423 = 134937
Step 320: 134937 + 423 = 135360
Step 321: 135360 + 423 = 135783
Step 322: 135783 + 423 = 136206
Step 323: 136206 + 423 = 136629
Step 324: 136629 + 423 = 137052
Step 325: 137052 + 423 = 137475
Step 326: 137475 + 423 = 137898
Step 327: 137898 + 423 = 138321
Step 328: 138321 + 423 = 138744
Step 329: 138744 + 423 = 139167
Step 330: 139167 + 423 = 139590
Step 331: 139590 + 423 = 140013
Step 332: 140013 + 423 = 140436
Step 333: 140436 + 423 = 140859
Step 334: 140859 + 423 = 141282
Step 335: 141282 + 423 = 141705
Step 336: 141705 + 423 = 142128
Step 337: 142128 + 423 = 142551
Step 338: 142551 + 423 = 142974
Step 339: 142974 + 423 = 143397
Step 340: 143397 + 423 = 143820
Step 341: 143820 + 423 = 144243
Step 342: 144243 + 423 = 144666
Step 343: 144666 + 423 = 145089
Step 344: 145089 + 423 = 145512
Step 345: 145512 + 423 = 145935
Step 346: 145935 + 423 = 146358
Step 347: 146358 + 423 = 146781
Step 348: 146781 + 423 = 147204
Step 349: 147204 + 423 = 147627
Step 350: 147627 + 423 = 148050
Step 351: 148050 + 423 = 148473
Step 352: 148473 + 423 = 148896
Step 353: 148896 + 423 = 149319
Step 354: 149319 + 423 = 149742
Step 355: 149742 + 423 = 150165
Step 356: 150165 + 423 = 150588
Step 357: 150588 + 423 = 151011
Step 358: 151011 + 423 = 151434
Step 359: 151434 + 423 = 151857
Step 360: 151857 + 423 = 152280
Step 361: 152280 + 423 = 152703
Step 362: 152703 + 423 = 153126
Step 363: 153126 + 423 = 153549
Step 364: 153549 + 423 = 153972
Step 365: 153972 + 423 = 154395
Step 366: 154395 + 423 = 154818
Step 367: 154818 + 423 = 155241
Step 368: 155241 + 423 = 155664
Step 369: 155664 + 423 = 156087
Step 370: 156087 + 423 = 156510
Step 371: 156510 + 423 = 156933
Step 372: 156933 + 423 = 157356
Step 373: 157356 + 423 = 157779
Step 374: 157779 + 423 = 158202
Step 375: 158202 + 423 = 158625
Step 376: 158625 + 423 = 159048
Step 377: 159048 + 423 = 159471
Step 378: 159471 + 423 = 159894
Step 379: 159894 + 423 = 160317
Step 380: 160317 + 423 = 160740
Step 381: 160740 + 423 = 161163
Step 382: 161163 + 423 = 161586
Step 383: 161586 + 423 = 162009
Step 384: 162009 + 423 = 162432
Step 385: 162432 + 423 = 162855
Step 386: 162855 + 423 = 163278
Step 387: 163278 + 423 = 163701
Step 388: 163701 + 423 = 164124
Step 389: 164124 + 423 = 164547
Step 390: 164547 + 423 = 164970
Step 391: 164970 + 423 = 165393
Step 392: 165393 + 423 = 165816
Step 393: 165816 + 423 = 166239
Step 394: 166239 + 423 = 166662
Step 395: 166662 + 423 = 167085
Step 396: 167085 + 423 = 167508
Step 397: 167508 + 423 = 167931
Step 398: 167931 + 423 = 168354
Step 399: 168354 + 423 = 168777
Step 400: 168777 + 423 = 169200
Step 401: 169200 + 423 = 169623
Step 402: 169623 + 423 = 170046
Step 403: 170046 + 423 = 170469
Step 404: 170469 + 423 = 170892
Step 405: 170892 + 423 = 171315
Step 406: 171315 + 423 = 171738
Step 407: 171738 + 423 = 172161
Step 408: 172161 + 423 = 172584
Step 409: 172584 + 423 = 173007

So, 423*409 = 173007