84579 ÷ 4 = 21144 R3
Let's divide 84579 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 (4) of the dividend behind the 0 and repeat the process: 4 / 4

Step 2:
4 goes into 4 1 times with a remainder of 0.
Write down 1 as next digit of of the result. 
Result so far: 21
Subtract 4 from 4 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: 211
Subtract 4 from 5 to get 1.
Bring next digit (7) of the dividend behind the 1 and repeat the process: 17 / 4

Step 4:
4 goes into 17 4 times with a remainder of 1.
Write down 4 as next digit of of the result. 
Result so far: 2114
Subtract 16 from 17 to get 1.
Bring next digit (9) of the dividend behind the 1 and repeat the process: 19 / 4

Step 5:
4 goes into 19 4 times with a remainder of 3.
Write down 4 as next digit of of the result. 
Result so far: 21144
Subtract 16 from 19 to get 3.

The final result is 21144 with a remainder of 3.