Alright, let's work through 56405349 times 20639023 step by step
56405349 × 20639023 = 20639023 × (56405349)
+ 20639023 × 9 yielding 185751207
+ 20639023 × 40 which equals 825560920
+ 20639023 × 300 that equals 6191706900
+ 20639023 × 5000 what gives us 103195115000
+ 20639023 × 00000 resulting in 0
+ 20639023 × 400000 what gives us 8255609200000
+ 20639023 × 6000000 yielding 123834138000000
+ 20639023 × 50000000 producing 1031951150000000

= 1164151295334027
