Alright, let's work through 81686749 times 3828488 step by step
81686749 × 3828488 = 3828488 × (81686749)
+ 3828488 × 9 resulting in 34456392
+ 3828488 × 40 yielding 153139520
+ 3828488 × 700 resulting in 2679941600
+ 3828488 × 6000 which equals 22970928000
+ 3828488 × 80000 yielding 306279040000
+ 3828488 × 600000 which equals 2297092800000
+ 3828488 × 1000000 that results in 3828488000000
+ 3828488 × 80000000 giving us 306279040000000

= 312736738305512
