Alright, let's work through 20997235 times 72715390 step by step
20997235 × 72715390 = 72715390 × (20997235)
+ 72715390 × 5 yielding 363576950
+ 72715390 × 30 that equals 2181461700
+ 72715390 × 200 producing 14543078000
+ 72715390 × 7000 which equals 509007730000
+ 72715390 × 90000 what gives us 6544385100000
+ 72715390 × 900000 resulting in 65443851000000
+ 72715390 × 0000000 yielding 0
+ 72715390 × 20000000 what gives us 1454307800000000

= 1526822131946650
