Alright, let's work through 50121007 times 77106016 step by step
50121007 × 77106016 = 77106016 × (50121007)
+ 77106016 × 7 resulting in 539742112
+ 77106016 × 00 what gives us 0
+ 77106016 × 000 resulting in 0
+ 77106016 × 1000 yielding 77106016000
+ 77106016 × 20000 that is equal 1542120320000
+ 77106016 × 100000 what gives us 7710601600000
+ 77106016 × 0000000 that equals 0
+ 77106016 × 50000000 yielding 3855300800000000

= 3864631167678112
