Alright, let's work through 20521986 times 21480313 step by step
20521986 × 21480313 = 21480313 × (20521986)
+ 21480313 × 6 that is equal 128881878
+ 21480313 × 80 that results in 1718425040
+ 21480313 × 900 that results in 19332281700
+ 21480313 × 1000 that results in 21480313000
+ 21480313 × 20000 that equals 429606260000
+ 21480313 × 500000 that results in 10740156500000
+ 21480313 × 0000000 yielding 0
+ 21480313 × 20000000 resulting in 429606260000000

= 440818682661618
