Alright, let's work through 64981798 times 39378529 step by step
64981798 × 39378529 = 39378529 × (64981798)
+ 39378529 × 8 that equals 315028232
+ 39378529 × 90 yielding 3544067610
+ 39378529 × 700 resulting in 27564970300
+ 39378529 × 1000 yielding 39378529000
+ 39378529 × 80000 producing 3150282320000
+ 39378529 × 900000 giving us 35440676100000
+ 39378529 × 4000000 that results in 157514116000000
+ 39378529 × 60000000 producing 2362711740000000

= 2558887617015142
