Alright, let's work through 86873674 times 89121068 step by step
86873674 × 89121068 = 89121068 × (86873674)
+ 89121068 × 4 giving us 356484272
+ 89121068 × 70 yielding 6238474760
+ 89121068 × 600 yielding 53472640800
+ 89121068 × 3000 resulting in 267363204000
+ 89121068 × 70000 yielding 6238474760000
+ 89121068 × 800000 that results in 71296854400000
+ 89121068 × 6000000 that equals 534726408000000
+ 89121068 × 80000000 that is equal 7129685440000000

= 7742274607963832
