We're dividing 210868 by 21 
We want to divide 210868 by 21.

Step 1:
21 can be fit into 2 0 times, resulting in a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 2 and we're left with 2.
Take the next digit (1) from the dividend and append it to 2, then repeat: 21 / 21

Going ahead to step 2:
The number 21 fits into 21 1 times, leaving a remainder of 0.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Deduct 21 from 21 and we're left with 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 21

Let's proceed to step 3:
21 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 10.0
Deduct 0 from 0 and we're left with 0.
Include the next digit (8) from the dividend after 0, then repeat: 8 / 21

Let's proceed to step 4:
21 goes into 8 0 times with a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 100.0
The remainder is 8 after subtracting 0 from 8.
Take the next digit (6) from the dividend and append it to 8, then repeat: 86 / 21

Step 5:
21 can be fit into 86 4 times, resulting in a remainder of 2.
Record the quotient 4 as the next digit in the result. 
Result so far: 1004.0
Subtract 84 from 86 to get 2.
Fetch the next digit (8) from the dividend, attach it to 2 and continue: 28 / 21

Advancing to step 6:
21 goes into 28 1 times with a remainder of 7.
Use 1 as the next digit of our solution. 
Result so far: 10041.0
If we take 21 away from 28, we end up with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Going ahead to step 7:
21 goes into 70 3 times with a remainder of 7.
Put 3 as the next digit of the answer. 
Result so far: 10041.3
If we take 63 away from 70, we end up with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

On to step 8:
21 goes into 70 3 times with a remainder of 7.
Record the quotient 3 as the next digit in the result. 
Result so far: 10041.33
Subtract 63 from 70 to get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

The quotient of the division is 10041.33, and the remainder is 0.007.