No problem, we've got 3969 and 1800 to multiply
3969 × 1800 = 1800 × (3969)
+ 1800 × 9 that is equal 16200
+ 1800 × 60 that is equal 108000
+ 1800 × 900 resulting in 1620000
+ 1800 × 3000 which equals 5400000

= 7144200
