Alright, let's work through 98968869 times 645791 step by step
98968869 × 645791 = 645791 × (98968869)
+ 645791 × 9 that is equal 5812119
+ 645791 × 60 that equals 38747460
+ 645791 × 800 that equals 516632800
+ 645791 × 8000 that equals 5166328000
+ 645791 × 60000 yielding 38747460000
+ 645791 × 900000 giving us 581211900000
+ 645791 × 8000000 that results in 5166328000000
+ 645791 × 90000000 that results in 58121190000000

= 63913204880379
