Alright, let's work through 9991 times 8114 step by step
9991 × 8114 = 8114 × (9991)
+ 8114 × 1 yielding 8114
+ 8114 × 90 giving us 730260
+ 8114 × 900 resulting in 7302600
+ 8114 × 9000 producing 73026000

= 81066974
