Alright, let's work through 78323237 times 20640537 step by step
78323237 × 20640537 = 20640537 × (78323237)
+ 20640537 × 7 that equals 144483759
+ 20640537 × 30 yielding 619216110
+ 20640537 × 200 yielding 4128107400
+ 20640537 × 3000 that results in 61921611000
+ 20640537 × 20000 that equals 412810740000
+ 20640537 × 300000 that is equal 6192161100000
+ 20640537 × 8000000 producing 165124296000000
+ 20640537 × 70000000 that results in 1444837590000000

= 1616633671258269
