Alright, let's work through 78067453 times 86420383 step by step
78067453 × 86420383 = 86420383 × (78067453)
+ 86420383 × 3 that equals 259261149
+ 86420383 × 50 producing 4321019150
+ 86420383 × 400 yielding 34568153200
+ 86420383 × 7000 that results in 604942681000
+ 86420383 × 60000 that equals 5185222980000
+ 86420383 × 000000 resulting in 0
+ 86420383 × 8000000 that equals 691363064000000
+ 86420383 × 70000000 what gives us 6049426810000000

= 6746619188094499
