Alright, let's work through 20159602 times 20841041 step by step
20159602 × 20841041 = 20841041 × (20159602)
+ 20841041 × 2 yielding 41682082
+ 20841041 × 00 that results in 0
+ 20841041 × 600 giving us 12504624600
+ 20841041 × 9000 producing 187569369000
+ 20841041 × 50000 what gives us 1042052050000
+ 20841041 × 100000 that results in 2084104100000
+ 20841041 × 0000000 what gives us 0
+ 20841041 × 20000000 that equals 416820820000000

= 420147091825682
