No problem, we've got 3921 and 5275 to multiply
3921 × 5275 = 5275 × (3921)
+ 5275 × 1 what gives us 5275
+ 5275 × 20 that results in 105500
+ 5275 × 900 what gives us 4747500
+ 5275 × 3000 giving us 15825000

= 20683275
