No problem, we've got 6499 and 663 to multiply
6499 × 663 = 663 × (6499)
+ 663 × 9 which equals 5967
+ 663 × 90 what gives us 59670
+ 663 × 400 what gives us 265200
+ 663 × 6000 resulting in 3978000

= 4308837
