Alright, let's work through 20158179 times 40353966 step by step
20158179 × 40353966 = 40353966 × (20158179)
+ 40353966 × 9 resulting in 363185694
+ 40353966 × 70 resulting in 2824777620
+ 40353966 × 100 that results in 4035396600
+ 40353966 × 8000 which equals 322831728000
+ 40353966 × 50000 which equals 2017698300000
+ 40353966 × 100000 what gives us 4035396600000
+ 40353966 × 0000000 resulting in 0
+ 40353966 × 20000000 producing 807079320000000

= 813462469987914
