Alright, let's work through 8157 times 6494 step by step
8157 × 6494 = 6494 × (8157)
+ 6494 × 7 that is equal 45458
+ 6494 × 50 giving us 324700
+ 6494 × 100 producing 649400
+ 6494 × 8000 yielding 51952000

= 52971558
