Alright, let's work through 8639 times 1165 step by step
8639 × 1165 = 1165 × (8639)
+ 1165 × 9 that results in 10485
+ 1165 × 30 that is equal 34950
+ 1165 × 600 what gives us 699000
+ 1165 × 8000 that equals 9320000

= 10064435
