Alright, let's work through 2643 times 2399 step by step
2643 × 2399 = 2399 × (2643)
+ 2399 × 3 that equals 7197
+ 2399 × 40 that equals 95960
+ 2399 × 600 producing 1439400
+ 2399 × 2000 yielding 4798000

= 6340557
