Alright, let's work through 8529 times 6423 step by step
8529 × 6423 = 6423 × (8529)
+ 6423 × 9 giving us 57807
+ 6423 × 20 resulting in 128460
+ 6423 × 500 which equals 3211500
+ 6423 × 8000 yielding 51384000

= 54781767
