Alright, let's work through 84240757 times 78087558 step by step
84240757 × 78087558 = 78087558 × (84240757)
+ 78087558 × 7 producing 546612906
+ 78087558 × 50 yielding 3904377900
+ 78087558 × 700 what gives us 54661290600
+ 78087558 × 0000 yielding 0
+ 78087558 × 40000 resulting in 3123502320000
+ 78087558 × 200000 producing 15617511600000
+ 78087558 × 4000000 which equals 312350232000000
+ 78087558 × 80000000 that equals 6247004640000000

= 6578154998201406
