Alright, let's work through 99512109 times 76831998 step by step
99512109 × 76831998 = 76831998 × (99512109)
+ 76831998 × 9 yielding 691487982
+ 76831998 × 00 yielding 0
+ 76831998 × 100 that equals 7683199800
+ 76831998 × 2000 that is equal 153663996000
+ 76831998 × 10000 what gives us 768319980000
+ 76831998 × 500000 giving us 38415999000000
+ 76831998 × 9000000 giving us 691487982000000
+ 76831998 × 90000000 that results in 6914879820000000

= 7645714159663782
