Alright, let's work through 66685871 times 81579697 step by step
66685871 × 81579697 = 81579697 × (66685871)
+ 81579697 × 1 yielding 81579697
+ 81579697 × 70 that equals 5710578790
+ 81579697 × 800 which equals 65263757600
+ 81579697 × 5000 yielding 407898485000
+ 81579697 × 80000 that is equal 6526375760000
+ 81579697 × 600000 that equals 48947818200000
+ 81579697 × 6000000 giving us 489478182000000
+ 81579697 × 60000000 producing 4894781820000000

= 5440213150361087
