Alright, let's work through 3921 times 3887 step by step
3921 × 3887 = 3887 × (3921)
+ 3887 × 1 producing 3887
+ 3887 × 20 resulting in 77740
+ 3887 × 900 giving us 3498300
+ 3887 × 3000 producing 11661000

= 15240927
