80580 ÷ 4 = 20145 R0
We're going to perform division on 80580 with 4 as the divisor.

Step 1:
4 goes into 8 2 times with a remainder of 0.
Write down 2 as next digit of of the result. 
Result so far: 2
Subtract 8 from 8 to get 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 4

Step 2:
4 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of of the result. 
Result so far: 20
Subtract 0 from 0 to get 0.
Bring next digit (5) of the dividend behind the 0 and repeat the process: 5 / 4

Step 3:
4 goes into 5 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 201
Subtract 4 from 5 to get 1.
Bring next digit (8) of the dividend behind the 1 and repeat the process: 18 / 4

Step 4:
4 goes into 18 4 times with a remainder of 2.
Write down 4 as next digit of of the result. 
Result so far: 2014
Subtract 16 from 18 to get 2.
Bring next digit (0) of the dividend behind the 2 and repeat the process: 20 / 4

Step 5:
4 goes into 20 5 times with a remainder of 0.
Write down 5 as next digit of of the result. 
Result so far: 20145
Subtract 20 from 20 to get 0.

The final result is 20145 with a remainder of 0.