72139 ÷ 8 = 9017 R3
We're going to perform division on 72139 with 8 as the divisor.

Step 1:
8 goes into 7 0 times with a remainder of 7.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 7 to get 7.
Bring next digit (2) of the dividend behind the 7 and repeat the process: 72 / 8

Step 2:
8 goes into 72 9 times with a remainder of 0.
Write down 9 as next digit of of the result. 
Result so far: 9
Subtract 72 from 72 to get 0.
Bring next digit (1) of the dividend behind the 0 and repeat the process: 1 / 8

Step 3:
8 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of of the result. 
Result so far: 90
Subtract 0 from 1 to get 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 8

Step 4:
8 goes into 13 1 times with a remainder of 5.
Write down 1 as next digit of of the result. 
Result so far: 901
Subtract 8 from 13 to get 5.
Bring next digit (9) of the dividend behind the 5 and repeat the process: 59 / 8

Step 5:
8 goes into 59 7 times with a remainder of 3.
Write down 7 as next digit of of the result. 
Result so far: 9017
Subtract 56 from 59 to get 3.

The final result is 9017 with a remainder of 3.