223144 divided by 21 
The aim is to understand the frequency of 21 in 223144.

Going ahead to step 1:
21 goes into 2 0 times with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 2 leaves us with 2.
Bring next digit (2) of the dividend behind the 2 and repeat the process: 22 / 21

Let's proceed to step 2:
The number 21 fits into 22 1 times, leaving a remainder of 1.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we take 21 away from 22, we end up with 1.
Take the next digit (3) from the dividend and append it to 1, then repeat: 13 / 21

Advancing to step 3:
13 divided by 21 is 0 with a remainder of 13.
Write down 0 as next digit of the result. 
Result so far: 10.0
The remainder is 13 after subtracting 0 from 13.
Fetch the next digit (1) from the dividend, attach it to 13 and continue: 131 / 21

Moving on to step 4:
131 divided by 21 is 6 with a remainder of 5.
The next digit of our result is 6. 
Result so far: 106.0
If we take 126 away from 131, we end up with 5.
Include the next digit (4) from the dividend after 5, then repeat: 54 / 21

Moving on to step 5:
The number 21 fits into 54 2 times, leaving a remainder of 12.
Record the quotient 2 as the next digit in the result. 
Result so far: 1062.0
If we subtract 42 from 54, we get 12.
Append the next digit (4) from the dividend to 12 and continue with: 124 / 21

On to step 6:
124 divided by 21 is 5 with a remainder of 19.
The next digit of our result is 5. 
Result so far: 10625.0
Subtract 105 from 124 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.

Let's proceed to step 7:
If we divide 190 by 21, we get 9 and a remainder of 1.
The next digit of our result is 9. 
Result so far: 10625.9
Subtracting 189 from 190 leaves us 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.

Let's proceed to step 8:
21 goes into 10 0 times with a remainder of 10.
Record the quotient 0 as the next digit in the result. 
Result so far: 10625.9
Subtract 0 from 10 to get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Let's proceed to step 9:
The number 21 fits into 100 4 times, leaving a remainder of 16.
Write down 4 as next digit of the result. 
Result so far: 10625.904
If we take 84 away from 100, we end up 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.

Step 10:
21 can be fit into 160 7 times, resulting in a remainder of 13.
Record the quotient 7 as the next digit in the result. 
Result so far: 10625.9047
The remainder is 13 after subtracting 147 from 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Let's proceed to step 11:
21 can be fit into 130 6 times, resulting in a remainder of 4.
The number 6 becomes the next digit in our result. 
Result so far: 10625.90476
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:
21 goes into 40 1 times with a remainder of 19.
The number 1 becomes the next digit in our result. 
Result so far: 10625.904761
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.

Let's proceed to step 13:
The number 21 fits into 190 9 times, leaving a remainder of 1.
Write down 9 as next digit of the result. 
Result so far: 10625.9047619
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.

Step 14:
21 can be fit into 10 0 times, resulting in a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 10625.9047619
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

After the division, we end up with 10625.9047619 and a remainder of 1e-08.