Alright, let's work through 8639 times 251 step by step
8639 × 251 = 251 × (8639)
+ 251 × 9 that equals 2259
+ 251 × 30 yielding 7530
+ 251 × 600 giving us 150600
+ 251 × 8000 that results in 2008000

= 2168389
