20856 ÷ 6 = 3476 R0
Let's divide 20856 by 6.

Step 1:
6 goes into 2 0 times with a remainder of 2.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 2 to get 2.
Bring next digit (0) of the dividend behind the 2 and repeat the process: 20 / 6

Step 2:
6 goes into 20 3 times with a remainder of 2.
Write down 3 as next digit of of the result. 
Result so far: 3
Subtract 18 from 20 to get 2.
Bring next digit (8) of the dividend behind the 2 and repeat the process: 28 / 6

Step 3:
6 goes into 28 4 times with a remainder of 4.
Write down 4 as next digit of of the result. 
Result so far: 34
Subtract 24 from 28 to get 4.
Bring next digit (5) of the dividend behind the 4 and repeat the process: 45 / 6

Step 4:
6 goes into 45 7 times with a remainder of 3.
Write down 7 as next digit of of the result. 
Result so far: 347
Subtract 42 from 45 to get 3.
Bring next digit (6) of the dividend behind the 3 and repeat the process: 36 / 6

Step 5:
6 goes into 36 6 times with a remainder of 0.
Write down 6 as next digit of of the result. 
Result so far: 3476
Subtract 36 from 36 to get 0.

The final result is 3476 with a remainder of 0.