Alright, let's work through 1639 times 3451 step by step
1639 × 3451 = 3451 × (1639)
+ 3451 × 9 giving us 31059
+ 3451 × 30 that is equal 103530
+ 3451 × 600 which equals 2070600
+ 3451 × 1000 which equals 3451000

= 5656189
