Alright, let's work through 8991 times 580 step by step
8991 × 580 = 580 × (8991)
+ 580 × 1 that equals 580
+ 580 × 90 resulting in 52200
+ 580 × 900 which equals 522000
+ 580 × 8000 yielding 4640000

= 5214780
