Alright, let's work through 87013457 times 75661671 step by step
87013457 × 75661671 = 75661671 × (87013457)
+ 75661671 × 7 that results in 529631697
+ 75661671 × 50 what gives us 3783083550
+ 75661671 × 400 producing 30264668400
+ 75661671 × 3000 giving us 226985013000
+ 75661671 × 10000 that equals 756616710000
+ 75661671 × 000000 yielding 0
+ 75661671 × 7000000 giving us 529631697000000
+ 75661671 × 80000000 that equals 6052933680000000

= 6583583556106647
