We look at the division of 830632 by 21 
The aim is to understand the frequency of 21 in 830632.

Advancing to step 1:
21 goes into 8 0 times with a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Grab the next digit (3) from the dividend, add it to 8, then carry on: 83 / 21

Advancing to step 2:
When dividing 83 by 21, we get 3 with a remainder of 20.
Write down 3 as next digit of the result. 
Result so far: 3.0
Subtract 63 from 83 to get 20.
Grab the next digit (0) from the dividend, add it to 20, then carry on: 200 / 21

Going ahead to step 3:
200 divided by 21 is 9 with a remainder of 11.
Write down 9 as next digit of the result. 
Result so far: 39.0
Subtracting 189 from 200 leaves us with 11.
Bring next digit (6) of the dividend behind the 11 and repeat the process: 116 / 21

On to step 4:
21 can be fit into 116 5 times, resulting in a remainder of 11.
Put 5 as the next digit of the answer. 
Result so far: 395.0
Subtract 105 from 116 to get 11.
Append the next digit (3) from the dividend to 11 and continue with: 113 / 21

Going ahead to step 5:
21 goes into 113 5 times with a remainder of 8.
Write down 5 as next digit of the result. 
Result so far: 3955.0
Deduct 105 from 113 and we're left with 8.
Append the next digit (2) from the dividend to 8 and continue with: 82 / 21

Let's proceed to step 6:
21 can be fit into 82 3 times, resulting in a remainder of 19.
Put 3 as the next digit of the answer. 
Result so far: 39553.0
Deduct 63 from 82 and we're left with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Advancing to step 7:
21 can be fit into 190 9 times, resulting in a remainder of 1.
The number 9 becomes the next digit in our result. 
Result so far: 39553.9
Subtract 189 from 190 to get 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 8:
The number 21 fits into 10 0 times, leaving a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 39553.9
Subtracting 0 from 10 leaves us 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.

Going ahead to step 9:
100 divided by 21 is 4 with a remainder of 16.
Put 4 as the next digit of the answer. 
Result so far: 39553.904
Subtracting 84 from 100 leaves us with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Advancing to step 10:
When dividing 160 by 21, we get 7 with a remainder of 13.
Record the quotient 7 as the next digit in the result. 
Result so far: 39553.9047
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.

Advancing to step 11:
21 goes into 130 6 times with a remainder of 4.
Put 6 as the next digit of the answer. 
Result so far: 39553.90476
Subtract 126 from 130 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Moving on to step 12:
If we divide 40 by 21, we get 1 and a remainder of 19.
Write down 1 as next digit of the result. 
Result so far: 39553.904761
Deduct 21 from 40 and we're left with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Step 13:
190 divided by 21 is 9 with a remainder of 1.
Write down 9 as next digit of the result. 
Result so far: 39553.9047619
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.

Moving on to step 14:
10 divided by 21 is 0 with a remainder of 10.
Write down 0 as next digit of the result. 
Result so far: 39553.9047619
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.

The quotient of the division is 39553.9047619, and the remainder is 1e-08.