Alright, let's work through 6639 times 1995 step by step
6639 × 1995 = 1995 × (6639)
+ 1995 × 9 that results in 17955
+ 1995 × 30 which equals 59850
+ 1995 × 600 resulting in 1197000
+ 1995 × 6000 what gives us 11970000

= 13244805
