No problem, we've got 3963 and 5087 to multiply
3963 × 5087 = 5087 × (3963)
+ 5087 × 3 resulting in 15261
+ 5087 × 60 producing 305220
+ 5087 × 900 giving us 4578300
+ 5087 × 3000 what gives us 15261000

= 20159781
