Alright, let's work through 21042873 times 13785332 step by step
21042873 × 13785332 = 13785332 × (21042873)
+ 13785332 × 3 producing 41355996
+ 13785332 × 70 what gives us 964973240
+ 13785332 × 800 yielding 11028265600
+ 13785332 × 2000 which equals 27570664000
+ 13785332 × 40000 producing 551413280000
+ 13785332 × 000000 that results in 0
+ 13785332 × 1000000 that results in 13785332000000
+ 13785332 × 20000000 resulting in 275706640000000

= 290082990538836
