12791 ÷ 9 = 1421 R2
Let's divide 12791 by 9.

Step 1:
9 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 1 to get 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 9

Step 2:
9 goes into 12 1 times with a remainder of 3.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 9 from 12 to get 3.
Bring next digit (7) of the dividend behind the 3 and repeat the process: 37 / 9

Step 3:
9 goes into 37 4 times with a remainder of 1.
Write down 4 as next digit of of the result. 
Result so far: 14
Subtract 36 from 37 to get 1.
Bring next digit (9) of the dividend behind the 1 and repeat the process: 19 / 9

Step 4:
9 goes into 19 2 times with a remainder of 1.
Write down 2 as next digit of of the result. 
Result so far: 142
Subtract 18 from 19 to get 1.
Bring next digit (1) of the dividend behind the 1 and repeat the process: 11 / 9

Step 5:
9 goes into 11 1 times with a remainder of 2.
Write down 1 as next digit of of the result. 
Result so far: 1421
Subtract 9 from 11 to get 2.

The final result is 1421 with a remainder of 2.