We look at the division of 517823 by 21 
We want to divide 517823 by 21.

Moving on to step 1:
The number 21 fits into 5 0 times, leaving a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 5 after subtracting 0 from 5.
Include the next digit (1) from the dividend after 5, then repeat: 51 / 21

Advancing to step 2:
21 goes into 51 2 times with a remainder of 9.
Put 2 as the next digit of the answer. 
Result so far: 2.0
The remainder is 9 after subtracting 42 from 51.
Grab the next digit (7) from the dividend, add it to 9, then carry on: 97 / 21

Advancing to step 3:
21 can be fit into 97 4 times, resulting in a remainder of 13.
The next digit of our result is 4. 
Result so far: 24.0
If we subtract 84 from 97, we get 13.
Include the next digit (8) from the dividend after 13, then repeat: 138 / 21

Step 4:
138 divided by 21 is 6 with a remainder of 12.
Record the quotient 6 as the next digit in the result. 
Result so far: 246.0
Subtract 126 from 138 to get 12.
Append the next digit (2) from the dividend to 12 and continue with: 122 / 21

Step 5:
The number 21 fits into 122 5 times, leaving a remainder of 17.
The number 5 becomes the next digit in our result. 
Result so far: 2465.0
If we subtract 105 from 122, we get 17.
Take the next digit (3) from the dividend and append it to 17, then repeat: 173 / 21

On to step 6:
If we divide 173 by 21, we get 8 and a remainder of 5.
Record the quotient 8 as the next digit in the result. 
Result so far: 24658.0
If we take 168 away from 173, we end up with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 7:
If we divide 50 by 21, we get 2 and a remainder of 8.
The number 2 becomes the next digit in our result. 
Result so far: 24658.2
Subtracting 42 from 50 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 8:
21 goes into 80 3 times with a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 24658.23
If we subtract 63 from 80, we get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Let's proceed to step 9:
The number 21 fits into 170 8 times, leaving a remainder of 2.
Use 8 as the next digit of our solution. 
Result so far: 24658.238
The remainder is 2 after subtracting 168 from 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Let's proceed to step 10:
21 can be fit into 20 0 times, resulting in a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 24658.238
The remainder is 20 after subtracting 0 from 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Moving on to step 11:
21 goes into 200 9 times with a remainder of 11.
The next digit of our result is 9. 
Result so far: 24658.23809
Deduct 189 from 200 and we're left with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Going ahead to step 12:
If we divide 110 by 21, we get 5 and a remainder of 5.
The next digit of our result is 5. 
Result so far: 24658.238095
Subtracting 105 from 110 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Let's proceed to step 13:
The number 21 fits into 50 2 times, leaving a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 24658.2380952
Deduct 42 from 50 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 14:
80 divided by 21 is 3 with a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 24658.23809523
The remainder is 17 after subtracting 63 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Our division results in 24658.23809523 with a remaining 1.7e-08.