Let's divide 21599699 by 781
The aim is to understand the frequency of 781 in 21599699.

Going ahead to step 1:
2 divided by 781 is 0 with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 2 and we're left with 2.
Take the next digit (1) from the dividend and append it to 2, then repeat: 21 / 781

Let's proceed to step 2:
The number 781 fits into 21 0 times, leaving a remainder of 21.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 21, we get 21.
Bring next digit (5) of the dividend behind the 21 and repeat the process: 215 / 781

On to step 3:
781 can be fit into 215 0 times, resulting in a remainder of 215.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 215 leaves us with 215.
Take the next digit (9) from the dividend and append it to 215, then repeat: 2159 / 781

On to step 4:
If we divide 2159 by 781, we get 2 and a remainder of 597.
Use 2 as the next digit of our solution. 
Result so far: 2.0
Subtracting 1562 from 2159 leaves us with 597.
Fetch the next digit (9) from the dividend, attach it to 597 and continue: 5979 / 781

Going ahead to step 5:
If we divide 5979 by 781, we get 7 and a remainder of 512.
The number 7 becomes the next digit in our result. 
Result so far: 27.0
Deduct 5467 from 5979 and we're left with 512.
Grab the next digit (6) from the dividend, add it to 512, then carry on: 5126 / 781

Advancing to step 6:
If we divide 5126 by 781, we get 6 and a remainder of 440.
Put 6 as the next digit of the answer. 
Result so far: 276.0
If we take 4686 away from 5126, we end up with 440.
Bring next digit (9) of the dividend behind the 440 and repeat the process: 4409 / 781

Going ahead to step 7:
When dividing 4409 by 781, we get 5 with a remainder of 504.
The next digit of our result is 5. 
Result so far: 2765.0
Subtract 3905 from 4409 to get 504.
Grab the next digit (9) from the dividend, add it to 504, then carry on: 5049 / 781

Advancing to step 8:
5049 divided by 781 is 6 with a remainder of 363.
Put 6 as the next digit of the answer. 
Result so far: 27656.0
If we take 4686 away from 5049, we end up with 363.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3630, and continue the process.

On to step 9:
781 goes into 3630 4 times with a remainder of 506.
The number 4 becomes the next digit in our result. 
Result so far: 27656.4
If we subtract 3124 from 3630, we get 506.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5060, and continue the process.

Step 10:
781 can be fit into 5060 6 times, resulting in a remainder of 374.
The next digit of our result is 6. 
Result so far: 27656.46
The remainder is 374 after subtracting 4686 from 5060.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3740, and continue the process.

Step 11:
When dividing 3740 by 781, we get 4 with a remainder of 616.
Use 4 as the next digit of our solution. 
Result so far: 27656.464
The remainder is 616 after subtracting 3124 from 3740.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6160, and continue the process.

Let's proceed to step 12:
781 goes into 6160 7 times with a remainder of 693.
Use 7 as the next digit of our solution. 
Result so far: 27656.4647
Subtracting 5467 from 6160 leaves us with 693.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6930, and continue the process.

Moving on to step 13:
The number 781 fits into 6930 8 times, leaving a remainder of 682.
The next digit of our result is 8. 
Result so far: 27656.46478
Deduct 6248 from 6930 and we're left with 682.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6820, and continue the process.

Step 14:
781 can be fit into 6820 8 times, resulting in a remainder of 572.
The next digit of our result is 8. 
Result so far: 27656.464788
If we subtract 6248 from 6820, we get 572.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5720, and continue the process.

The final outcome is 27656.464788, with a leftover of 5.72e-05.