No problem, we've got 3994 and 5188 to multiply
3994 × 5188 = 5188 × (3994)
+ 5188 × 4 that results in 20752
+ 5188 × 90 that is equal 466920
+ 5188 × 900 that is equal 4669200
+ 5188 × 3000 producing 15564000

= 20720872
