Alright, let's work through 99138371 times 79751018 step by step
99138371 × 79751018 = 79751018 × (99138371)
+ 79751018 × 1 giving us 79751018
+ 79751018 × 70 that is equal 5582571260
+ 79751018 × 300 resulting in 23925305400
+ 79751018 × 8000 that equals 638008144000
+ 79751018 × 30000 which equals 2392530540000
+ 79751018 × 100000 giving us 7975101800000
+ 79751018 × 9000000 which equals 717759162000000
+ 79751018 × 90000000 resulting in 7177591620000000

= 7906386010111678
