Alright, let's work through 81681355 times 76680057 step by step
81681355 × 76680057 = 76680057 × (81681355)
+ 76680057 × 5 that equals 383400285
+ 76680057 × 50 resulting in 3834002850
+ 76680057 × 300 producing 23004017100
+ 76680057 × 1000 producing 76680057000
+ 76680057 × 80000 which equals 6134404560000
+ 76680057 × 600000 resulting in 46008034200000
+ 76680057 × 1000000 resulting in 76680057000000
+ 76680057 × 80000000 yielding 6134404560000000

= 6263330957237235
