Alright, let's work through 51908373 times 99881951 step by step
51908373 × 99881951 = 99881951 × (51908373)
+ 99881951 × 3 that is equal 299645853
+ 99881951 × 70 that equals 6991736570
+ 99881951 × 300 which equals 29964585300
+ 99881951 × 8000 that results in 799055608000
+ 99881951 × 00000 which equals 0
+ 99881951 × 900000 that equals 89893755900000
+ 99881951 × 1000000 that equals 99881951000000
+ 99881951 × 50000000 that results in 4994097550000000

= 5184709568475723
