Alright, let's work through 4179 times 3999 step by step
4179 × 3999 = 3999 × (4179)
+ 3999 × 9 that is equal 35991
+ 3999 × 70 that is equal 279930
+ 3999 × 100 that equals 399900
+ 3999 × 4000 producing 15996000

= 16711821
