Alright, let's work through 8639 times 8536 step by step
8639 × 8536 = 8536 × (8639)
+ 8536 × 9 resulting in 76824
+ 8536 × 30 yielding 256080
+ 8536 × 600 that is equal 5121600
+ 8536 × 8000 that equals 68288000

= 73742504
