Alright, let's work through 78765393 times 46978613 step by step
78765393 × 46978613 = 46978613 × (78765393)
+ 46978613 × 3 that equals 140935839
+ 46978613 × 90 yielding 4228075170
+ 46978613 × 300 giving us 14093583900
+ 46978613 × 5000 that results in 234893065000
+ 46978613 × 60000 yielding 2818716780000
+ 46978613 × 700000 yielding 32885029100000
+ 46978613 × 8000000 what gives us 375828904000000
+ 46978613 × 70000000 resulting in 3288502910000000

= 3700288915539909
