No problem, we've got 6399 and 440 to multiply
6399 × 440 = 440 × (6399)
+ 440 × 9 that equals 3960
+ 440 × 90 that is equal 39600
+ 440 × 300 giving us 132000
+ 440 × 6000 that results in 2640000

= 2815560
