Alright, let's work through 20803394 times 51210419 step by step
20803394 × 51210419 = 51210419 × (20803394)
+ 51210419 × 4 that equals 204841676
+ 51210419 × 90 that results in 4608937710
+ 51210419 × 300 resulting in 15363125700
+ 51210419 × 3000 what gives us 153631257000
+ 51210419 × 00000 yielding 0
+ 51210419 × 800000 yielding 40968335200000
+ 51210419 × 0000000 that is equal 0
+ 51210419 × 20000000 resulting in 1024208380000000

= 1065350523362086
