Alright, let's work through 81518924 times 12763351 step by step
81518924 × 12763351 = 12763351 × (81518924)
+ 12763351 × 4 that equals 51053404
+ 12763351 × 20 producing 255267020
+ 12763351 × 900 which equals 11487015900
+ 12763351 × 8000 that equals 102106808000
+ 12763351 × 10000 that is equal 127633510000
+ 12763351 × 500000 what gives us 6381675500000
+ 12763351 × 1000000 what gives us 12763351000000
+ 12763351 × 80000000 producing 1021068080000000

= 1040454640154324
