We divide 856862 by 21
The aim is to understand the frequency of 21 in 856862.

On to step 1:
21 can be fit into 8 0 times, resulting in a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Grab the next digit (5) from the dividend, add it to 8, then carry on: 85 / 21

Let's proceed to step 2:
85 divided by 21 is 4 with a remainder of 1.
The next digit of our result is 4. 
Result so far: 4.0
Subtract 84 from 85 to get 1.
Append the next digit (6) from the dividend to 1 and continue with: 16 / 21

Let's proceed to step 3:
When dividing 16 by 21, we get 0 with a remainder of 16.
The next digit of our result is 0. 
Result so far: 40.0
Deduct 0 from 16 and we're left with 16.
Bring next digit (8) of the dividend behind the 16 and repeat the process: 168 / 21

Moving on to step 4:
21 goes into 168 8 times with a remainder of 0.
Use 8 as the next digit of our solution. 
Result so far: 408.0
Deduct 168 from 168 and we're left with 0.
Grab the next digit (6) from the dividend, add it to 0, then carry on: 6 / 21

Let's proceed to step 5:
21 can be fit into 6 0 times, resulting in a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 4080.0
If we take 0 away from 6, we end up with 6.
Grab the next digit (2) from the dividend, add it to 6, then carry on: 62 / 21

Moving on to step 6:
21 goes into 62 2 times with a remainder of 20.
The next digit of our result is 2. 
Result so far: 40802.0
The remainder is 20 after subtracting 42 from 62.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 7:
21 can be fit into 200 9 times, resulting in a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 40802.9
If we subtract 189 from 200, we get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Let's proceed to step 8:
21 can be fit into 110 5 times, resulting in a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 40802.95
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.

Step 9:
50 divided by 21 is 2 with a remainder of 8.
The next digit of our result is 2. 
Result so far: 40802.952
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.

Step 10:
21 goes into 80 3 times with a remainder of 17.
The number 3 becomes the next digit in our result. 
Result so far: 40802.9523
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.

Step 11:
21 can be fit into 170 8 times, resulting in a remainder of 2.
The next digit of our result is 8. 
Result so far: 40802.95238
If we subtract 168 from 170, we get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Moving on to step 12:
The number 21 fits into 20 0 times, leaving a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 40802.95238
If we take 0 away from 20, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Advancing to step 13:
When dividing 200 by 21, we get 9 with a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 40802.9523809
Subtracting 189 from 200 leaves us 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.

On to step 14:
21 can be fit into 110 5 times, resulting in a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 40802.95238095
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.

After the division, we end up with 40802.95238095 and a remainder of 5e-09.