Alright, let's work through 8520 times 8423 step by step
8520 × 8423 = 8423 × (8520)
+ 8423 × 0 that equals 0
+ 8423 × 20 yielding 168460
+ 8423 × 500 that equals 4211500
+ 8423 × 8000 giving us 67384000

= 71763960
