Alright, let's work through 21016571 times 75383471 step by step
21016571 × 75383471 = 75383471 × (21016571)
+ 75383471 × 1 that results in 75383471
+ 75383471 × 70 what gives us 5276842970
+ 75383471 × 500 that results in 37691735500
+ 75383471 × 6000 what gives us 452300826000
+ 75383471 × 10000 yielding 753834710000
+ 75383471 × 000000 which equals 0
+ 75383471 × 1000000 that is equal 75383471000000
+ 75383471 × 20000000 what gives us 1507669420000000

= 1584302070497941
