Alright, let's work through 8157 times 2485 step by step
8157 × 2485 = 2485 × (8157)
+ 2485 × 7 that equals 17395
+ 2485 × 50 giving us 124250
+ 2485 × 100 what gives us 248500
+ 2485 × 8000 that is equal 19880000

= 20270145
