Alright, let's work through 21502414 times 87340721 step by step
21502414 × 87340721 = 87340721 × (21502414)
+ 87340721 × 4 producing 349362884
+ 87340721 × 10 yielding 873407210
+ 87340721 × 400 that results in 34936288400
+ 87340721 × 2000 yielding 174681442000
+ 87340721 × 00000 resulting in 0
+ 87340721 × 500000 what gives us 43670360500000
+ 87340721 × 1000000 resulting in 87340721000000
+ 87340721 × 20000000 giving us 1746814420000000

= 1878036342000494
