857728 divided by 21 
Let's see how many times 21 fits into 857728.

Step 1:
If we divide 8 by 21, we get 0 and a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Bring next digit (5) of the dividend behind the 8 and repeat the process: 85 / 21

Moving on to step 2:
21 goes into 85 4 times with a remainder of 1.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
Deduct 84 from 85 and we're left with 1.
Fetch the next digit (7) from the dividend, attach it to 1 and continue: 17 / 21

Moving on to step 3:
The number 21 fits into 17 0 times, leaving a remainder of 17.
Record the quotient 0 as the next digit in the result. 
Result so far: 40.0
The remainder is 17 after subtracting 0 from 17.
Append the next digit (7) from the dividend to 17 and continue with: 177 / 21

On to step 4:
The number 21 fits into 177 8 times, leaving a remainder of 9.
Use 8 as the next digit of our solution. 
Result so far: 408.0
Deduct 168 from 177 and we're left with 9.
Fetch the next digit (2) from the dividend, attach it to 9 and continue: 92 / 21

Advancing to step 5:
92 divided by 21 is 4 with a remainder of 8.
Put 4 as the next digit of the answer. 
Result so far: 4084.0
Deduct 84 from 92 and we're left with 8.
Bring next digit (8) of the dividend behind the 8 and repeat the process: 88 / 21

Going ahead to step 6:
21 can be fit into 88 4 times, resulting in a remainder of 4.
The next digit of our result is 4. 
Result so far: 40844.0
Deduct 84 from 88 and we're left with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 7:
21 goes into 40 1 times with a remainder of 19.
The number 1 becomes the next digit in our result. 
Result so far: 40844.1
Subtract 21 from 40 to get 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

On to step 8:
21 can be fit into 190 9 times, resulting in a remainder of 1.
Use 9 as the next digit of our solution. 
Result so far: 40844.19
Deduct 189 from 190 and we're left with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Going ahead to step 9:
When dividing 10 by 21, we get 0 with a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 40844.19
Deduct 0 from 10 and we're left with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Moving on to step 10:
If we divide 100 by 21, we get 4 and a remainder of 16.
The next digit of our result is 4. 
Result so far: 40844.1904
The remainder is 16 after subtracting 84 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Step 11:
If we divide 160 by 21, we get 7 and a remainder of 13.
Record the quotient 7 as the next digit in the result. 
Result so far: 40844.19047
Subtracting 147 from 160 leaves us with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Moving on to step 12:
130 divided by 21 is 6 with a remainder of 4.
Put 6 as the next digit of the answer. 
Result so far: 40844.190476
Deduct 126 from 130 and we're left with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Step 13:
21 goes into 40 1 times with a remainder of 19.
The number 1 becomes the next digit in our result. 
Result so far: 40844.1904761
The remainder is 19 after subtracting 21 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Going ahead to step 14:
When dividing 190 by 21, we get 9 with a remainder of 1.
The number 9 becomes the next digit in our result. 
Result so far: 40844.19047619
If we take 189 away from 190, we end up with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Our division results in 40844.19047619 with a remaining 1e-09.