Alright, let's work through 8491 times 8540 step by step
8491 × 8540 = 8540 × (8491)
+ 8540 × 1 what gives us 8540
+ 8540 × 90 that results in 768600
+ 8540 × 400 yielding 3416000
+ 8540 × 8000 that is equal 68320000

= 72513140
