Alright, let's work through 3945329 times 20669816 step by step
3945329 × 20669816 = 20669816 × (3945329)
+ 20669816 × 9 that equals 186028344
+ 20669816 × 20 producing 413396320
+ 20669816 × 300 what gives us 6200944800
+ 20669816 × 5000 yielding 103349080000
+ 20669816 × 40000 producing 826792640000
+ 20669816 × 900000 which equals 18602834400000
+ 20669816 × 3000000 producing 62009448000000

= 81549224489464
