Alright, let's work through 20681070 times 51647693 step by step
20681070 × 51647693 = 51647693 × (20681070)
+ 51647693 × 0 giving us 0
+ 51647693 × 70 which equals 3615338510
+ 51647693 × 000 yielding 0
+ 51647693 × 1000 that is equal 51647693000
+ 51647693 × 80000 giving us 4131815440000
+ 51647693 × 600000 giving us 30988615800000
+ 51647693 × 0000000 resulting in 0
+ 51647693 × 20000000 producing 1032953860000000

= 1068129554271510
