Alright, let's work through 8416 times 1636 step by step
8416 × 1636 = 1636 × (8416)
+ 1636 × 6 giving us 9816
+ 1636 × 10 what gives us 16360
+ 1636 × 400 that is equal 654400
+ 1636 × 8000 what gives us 13088000

= 13768576
