Alright, let's work through 15857371 times 42751431 step by step
15857371 × 42751431 = 42751431 × (15857371)
+ 42751431 × 1 producing 42751431
+ 42751431 × 70 that is equal 2992600170
+ 42751431 × 300 what gives us 12825429300
+ 42751431 × 7000 that equals 299260017000
+ 42751431 × 50000 producing 2137571550000
+ 42751431 × 800000 producing 34201144800000
+ 42751431 × 5000000 yielding 213757155000000
+ 42751431 × 10000000 what gives us 427514310000000

= 677925302147901
