No problem, we've got 4028 and 5381 to multiply
4028 × 5381 = 5381 × (4028)
+ 5381 × 8 what gives us 43048
+ 5381 × 20 yielding 107620
+ 5381 × 000 what gives us 0
+ 5381 × 4000 what gives us 21524000

= 21674668
