Alright, let's work through 3418421 times 81072531 step by step
3418421 × 81072531 = 81072531 × (3418421)
+ 81072531 × 1 producing 81072531
+ 81072531 × 20 giving us 1621450620
+ 81072531 × 400 producing 32429012400
+ 81072531 × 8000 producing 648580248000
+ 81072531 × 10000 that is equal 810725310000
+ 81072531 × 400000 producing 32429012400000
+ 81072531 × 3000000 giving us 243217593000000

= 277140042493551
