Alright, let's work through 89543872 times 49778986 step by step
89543872 × 49778986 = 49778986 × (89543872)
+ 49778986 × 2 yielding 99557972
+ 49778986 × 70 that equals 3484529020
+ 49778986 × 800 that equals 39823188800
+ 49778986 × 3000 that results in 149336958000
+ 49778986 × 40000 giving us 1991159440000
+ 49778986 × 500000 yielding 24889493000000
+ 49778986 × 9000000 yielding 448010874000000
+ 49778986 × 80000000 that results in 3982318880000000

= 4457403150673792
