Alright, let's work through 81186874 times 12540998 step by step
81186874 × 12540998 = 12540998 × (81186874)
+ 12540998 × 4 that results in 50163992
+ 12540998 × 70 giving us 877869860
+ 12540998 × 800 giving us 10032798400
+ 12540998 × 6000 what gives us 75245988000
+ 12540998 × 80000 which equals 1003279840000
+ 12540998 × 100000 yielding 1254099800000
+ 12540998 × 1000000 which equals 12540998000000
+ 12540998 × 80000000 that results in 1003279840000000

= 1018164424460252
