Alright, let's work through 7865 times 3991 step by step
7865 × 3991 = 3991 × (7865)
+ 3991 × 5 what gives us 19955
+ 3991 × 60 that is equal 239460
+ 3991 × 800 that equals 3192800
+ 3991 × 7000 that is equal 27937000

= 31389215
