Alright, let's work through 1639 times 1722 step by step
1639 × 1722 = 1722 × (1639)
+ 1722 × 9 resulting in 15498
+ 1722 × 30 yielding 51660
+ 1722 × 600 which equals 1033200
+ 1722 × 1000 producing 1722000

= 2822358
