Alright, let's work through 5751 times 2398 step by step
5751 × 2398 = 2398 × (5751)
+ 2398 × 1 that results in 2398
+ 2398 × 50 that results in 119900
+ 2398 × 700 resulting in 1678600
+ 2398 × 5000 yielding 11990000

= 13790898
