We look at the division of 531936 by 21 
We want to divide 531936 by 21.

On to step 1:
When dividing 5 by 21, we get 0 with a remainder of 5.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 5 after subtracting 0 from 5.
Append the next digit (3) from the dividend to 5 and continue with: 53 / 21

On to step 2:
53 divided by 21 is 2 with a remainder of 11.
Write down 2 as next digit of the result. 
Result so far: 2.0
Subtract 42 from 53 to get 11.
Bring next digit (1) of the dividend behind the 11 and repeat the process: 111 / 21

Going ahead to step 3:
111 divided by 21 is 5 with a remainder of 6.
Write down 5 as next digit of the result. 
Result so far: 25.0
Subtracting 105 from 111 leaves us with 6.
Grab the next digit (9) from the dividend, add it to 6, then carry on: 69 / 21

Advancing to step 4:
When dividing 69 by 21, we get 3 with a remainder of 6.
Write down 3 as next digit of the result. 
Result so far: 253.0
If we take 63 away from 69, we end up with 6.
Take the next digit (3) from the dividend and append it to 6, then repeat: 63 / 21

Moving on to step 5:
The number 21 fits into 63 3 times, leaving a remainder of 0.
Record the quotient 3 as the next digit in the result. 
Result so far: 2533.0
Subtract 63 from 63 to get 0.
Include the next digit (6) from the dividend after 0, then repeat: 6 / 21

Moving on to step 6:
21 can be fit into 6 0 times, resulting in a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 25330.0
Deduct 0 from 6 and we're left with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 7:
The number 21 fits into 60 2 times, leaving a remainder of 18.
The next digit of our result is 2. 
Result so far: 25330.2
Deduct 42 from 60 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Moving on to step 8:
When dividing 180 by 21, we get 8 with a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 25330.28
If we subtract 168 from 180, we get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Let's proceed to step 9:
The number 21 fits into 120 5 times, leaving a remainder of 15.
The number 5 becomes the next digit in our result. 
Result so far: 25330.285
The remainder is 15 after subtracting 105 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Step 10:
If we divide 150 by 21, we get 7 and a remainder of 3.
The next digit of our result is 7. 
Result so far: 25330.2857
If we take 147 away from 150, we end up with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 11:
21 can be fit into 30 1 times, resulting in a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 25330.28571
Deduct 21 from 30 and we're left with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Let's proceed to step 12:
21 can be fit into 90 4 times, resulting in a remainder of 6.
Put 4 as the next digit of the answer. 
Result so far: 25330.285714
The remainder is 6 after subtracting 84 from 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 13:
21 can be fit into 60 2 times, resulting in a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 25330.2857142
Deduct 42 from 60 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

On to step 14:
21 can be fit into 180 8 times, resulting in a remainder of 12.
The number 8 becomes the next digit in our result. 
Result so far: 25330.28571428
The remainder is 12 after subtracting 168 from 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

The final outcome is 25330.28571428, with a leftover of 1.2e-08.