Alright, let's work through 51513140 times 65651891 step by step
51513140 × 65651891 = 65651891 × (51513140)
+ 65651891 × 0 yielding 0
+ 65651891 × 40 what gives us 2626075640
+ 65651891 × 100 giving us 6565189100
+ 65651891 × 3000 giving us 196955673000
+ 65651891 × 10000 giving us 656518910000
+ 65651891 × 500000 resulting in 32825945500000
+ 65651891 × 1000000 which equals 65651891000000
+ 65651891 × 50000000 giving us 3282594550000000

= 3381935052347740
