Alright, let's work through 81209031 times 82991245 step by step
81209031 × 82991245 = 82991245 × (81209031)
+ 82991245 × 1 producing 82991245
+ 82991245 × 30 producing 2489737350
+ 82991245 × 000 what gives us 0
+ 82991245 × 9000 that equals 746921205000
+ 82991245 × 00000 resulting in 0
+ 82991245 × 200000 that results in 16598249000000
+ 82991245 × 1000000 resulting in 82991245000000
+ 82991245 × 80000000 that is equal 6639299600000000

= 6739638587933595
