Alright, let's work through 2042 times 5638 step by step
2042 × 5638 = 5638 × (2042)
+ 5638 × 2 that is equal 11276
+ 5638 × 40 producing 225520
+ 5638 × 000 producing 0
+ 5638 × 2000 producing 11276000

= 11512796
