Alright, let's work through 8638 times 7479 step by step
8638 × 7479 = 7479 × (8638)
+ 7479 × 8 resulting in 59832
+ 7479 × 30 that results in 224370
+ 7479 × 600 yielding 4487400
+ 7479 × 8000 which equals 59832000

= 64603602
