Alright, let's work through 87166479 times 86342051 step by step
87166479 × 86342051 = 86342051 × (87166479)
+ 86342051 × 9 that is equal 777078459
+ 86342051 × 70 resulting in 6043943570
+ 86342051 × 400 that is equal 34536820400
+ 86342051 × 6000 what gives us 518052306000
+ 86342051 × 60000 which equals 5180523060000
+ 86342051 × 100000 that is equal 8634205100000
+ 86342051 × 7000000 giving us 604394357000000
+ 86342051 × 80000000 yielding 6907364080000000

= 7526132575308429
