Alright, let's work through 3670887 times 81636112 step by step
3670887 × 81636112 = 81636112 × (3670887)
+ 81636112 × 7 yielding 571452784
+ 81636112 × 80 that results in 6530888960
+ 81636112 × 800 that is equal 65308889600
+ 81636112 × 0000 yielding 0
+ 81636112 × 70000 giving us 5714527840000
+ 81636112 × 600000 resulting in 48981667200000
+ 81636112 × 3000000 giving us 244908336000000

= 299676942271344
