Alright, let's work through 78815655 times 70452868 step by step
78815655 × 70452868 = 70452868 × (78815655)
+ 70452868 × 5 resulting in 352264340
+ 70452868 × 50 giving us 3522643400
+ 70452868 × 600 that equals 42271720800
+ 70452868 × 5000 that equals 352264340000
+ 70452868 × 10000 what gives us 704528680000
+ 70452868 × 800000 yielding 56362294400000
+ 70452868 × 8000000 producing 563622944000000
+ 70452868 × 70000000 giving us 4931700760000000

= 5552788938048540
