77391 ÷ 5 = 15478 R1
We're going to perform division on 77391 with 5 as the divisor.

Step 1:
5 goes into 7 1 times with a remainder of 2.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 5 from 7 to get 2.
Bring next digit (7) of the dividend behind the 2 and repeat the process: 27 / 5

Step 2:
5 goes into 27 5 times with a remainder of 2.
Write down 5 as next digit of of the result. 
Result so far: 15
Subtract 25 from 27 to get 2.
Bring next digit (3) of the dividend behind the 2 and repeat the process: 23 / 5

Step 3:
5 goes into 23 4 times with a remainder of 3.
Write down 4 as next digit of of the result. 
Result so far: 154
Subtract 20 from 23 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 5

Step 4:
5 goes into 39 7 times with a remainder of 4.
Write down 7 as next digit of of the result. 
Result so far: 1547
Subtract 35 from 39 to get 4.
Bring next digit (1) of the dividend behind the 4 and repeat the process: 41 / 5

Step 5:
5 goes into 41 8 times with a remainder of 1.
Write down 8 as next digit of of the result. 
Result so far: 15478
Subtract 40 from 41 to get 1.

The final result is 15478 with a remainder of 1.