Alright, let's work through 678419 times 68478839 step by step
678419 × 68478839 = 68478839 × (678419)
+ 68478839 × 9 producing 616309551
+ 68478839 × 10 producing 684788390
+ 68478839 × 400 which equals 27391535600
+ 68478839 × 8000 that equals 547830712000
+ 68478839 × 70000 yielding 4793518730000
+ 68478839 × 600000 that equals 41087303400000

= 46457345475541
