No problem, we've got 3991 and 4358 to multiply
3991 × 4358 = 4358 × (3991)
+ 4358 × 1 what gives us 4358
+ 4358 × 90 resulting in 392220
+ 4358 × 900 that is equal 3922200
+ 4358 × 3000 giving us 13074000

= 17392778
