No problem, we've got 1669 and 7923 to multiply
1669 × 7923 = 7923 × (1669)
+ 7923 × 9 what gives us 71307
+ 7923 × 60 resulting in 475380
+ 7923 × 600 that equals 4753800
+ 7923 × 1000 which equals 7923000

= 13223487
