Alright, let's work through 8661 times 9039 step by step
8661 × 9039 = 9039 × (8661)
+ 9039 × 1 what gives us 9039
+ 9039 × 60 which equals 542340
+ 9039 × 600 that is equal 5423400
+ 9039 × 8000 that equals 72312000

= 78286779
