Alright, let's work through 81249818 times 79529782 step by step
81249818 × 79529782 = 79529782 × (81249818)
+ 79529782 × 8 yielding 636238256
+ 79529782 × 10 resulting in 795297820
+ 79529782 × 800 producing 63623825600
+ 79529782 × 9000 which equals 715768038000
+ 79529782 × 40000 what gives us 3181191280000
+ 79529782 × 200000 yielding 15905956400000
+ 79529782 × 1000000 producing 79529782000000
+ 79529782 × 80000000 yielding 6362382560000000

= 6461780313079676
