Alright, let's work through 78356580 times 12918328 step by step
78356580 × 12918328 = 12918328 × (78356580)
+ 12918328 × 0 that equals 0
+ 12918328 × 80 that is equal 1033466240
+ 12918328 × 500 which equals 6459164000
+ 12918328 × 6000 producing 77509968000
+ 12918328 × 50000 giving us 645916400000
+ 12918328 × 300000 that is equal 3875498400000
+ 12918328 × 8000000 producing 103346624000000
+ 12918328 × 70000000 that equals 904282960000000

= 1012236001398240
