81570 ÷ 4 = 20392 R2
Let's divide 81570 by 4.

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 (1) of the dividend behind the 0 and repeat the process: 1 / 4

Step 2:
4 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of of the result. 
Result so far: 20
Subtract 0 from 1 to get 1.
Bring next digit (5) of the dividend behind the 1 and repeat the process: 15 / 4

Step 3:
4 goes into 15 3 times with a remainder of 3.
Write down 3 as next digit of of the result. 
Result so far: 203
Subtract 12 from 15 to get 3.
Bring next digit (7) of the dividend behind the 3 and repeat the process: 37 / 4

Step 4:
4 goes into 37 9 times with a remainder of 1.
Write down 9 as next digit of of the result. 
Result so far: 2039
Subtract 36 from 37 to get 1.
Bring next digit (0) of the dividend behind the 1 and repeat the process: 10 / 4

Step 5:
4 goes into 10 2 times with a remainder of 2.
Write down 2 as next digit of of the result. 
Result so far: 20392
Subtract 8 from 10 to get 2.

The final result is 20392 with a remainder of 2.