Alright, let's work through 21165257 times 17957005 step by step
21165257 × 17957005 = 17957005 × (21165257)
+ 17957005 × 7 that equals 125699035
+ 17957005 × 50 that is equal 897850250
+ 17957005 × 200 resulting in 3591401000
+ 17957005 × 5000 which equals 89785025000
+ 17957005 × 60000 yielding 1077420300000
+ 17957005 × 100000 that equals 1795700500000
+ 17957005 × 1000000 producing 17957005000000
+ 17957005 × 20000000 what gives us 359140100000000

= 380064625775285
