Alright, let's work through 8391 times 2820 step by step
8391 × 2820 = 2820 × (8391)
+ 2820 × 1 producing 2820
+ 2820 × 90 resulting in 253800
+ 2820 × 300 that equals 846000
+ 2820 × 8000 yielding 22560000

= 23662620
