Alright, let's work through 8638 times 6409 step by step
8638 × 6409 = 6409 × (8638)
+ 6409 × 8 yielding 51272
+ 6409 × 30 resulting in 192270
+ 6409 × 600 what gives us 3845400
+ 6409 × 8000 what gives us 51272000

= 55360942
