We divide 644648 by 23
The aim is to understand the frequency of 23 in 644648.

Advancing to step 1:
6 divided by 23 is 0 with a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Append the next digit (4) from the dividend to 6 and continue with: 64 / 23

Going ahead to step 2:
When dividing 64 by 23, we get 2 with a remainder of 18.
Write down 2 as next digit of the result. 
Result so far: 2.0
Subtract 46 from 64 to get 18.
Include the next digit (4) from the dividend after 18, then repeat: 184 / 23

Step 3:
23 goes into 184 8 times with a remainder of 0.
Record the quotient 8 as the next digit in the result. 
Result so far: 28.0
The remainder is 0 after subtracting 184 from 184.
Include the next digit (6) from the dividend after 0, then repeat: 6 / 23

Step 4:
If we divide 6 by 23, we get 0 and a remainder of 6.
The number 0 becomes the next digit in our result. 
Result so far: 280.0
If we subtract 0 from 6, we get 6.
Fetch the next digit (4) from the dividend, attach it to 6 and continue: 64 / 23

Advancing to step 5:
23 can be fit into 64 2 times, resulting in a remainder of 18.
Use 2 as the next digit of our solution. 
Result so far: 2802.0
Subtract 46 from 64 to get 18.
Grab the next digit (8) from the dividend, add it to 18, then carry on: 188 / 23

On to step 6:
23 can be fit into 188 8 times, resulting in a remainder of 4.
Put 8 as the next digit of the answer. 
Result so far: 28028.0
Subtracting 184 from 188 leaves us 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 7:
40 divided by 23 is 1 with a remainder of 17.
Use 1 as the next digit of our solution. 
Result so far: 28028.1
Subtract 23 from 40 to 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.

Moving on to step 8:
If we divide 170 by 23, we get 7 and a remainder of 9.
Record the quotient 7 as the next digit in the result. 
Result so far: 28028.17
The remainder is 9 after subtracting 161 from 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Advancing to step 9:
When dividing 90 by 23, we get 3 with a remainder of 21.
Use 3 as the next digit of our solution. 
Result so far: 28028.173
Subtract 69 from 90 to get 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Moving on to step 10:
The number 23 fits into 210 9 times, leaving a remainder of 3.
Record the quotient 9 as the next digit in the result. 
Result so far: 28028.1739
Deduct 207 from 210 and we're left with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Moving on to step 11:
23 can be fit into 30 1 times, resulting in a remainder of 7.
Record the quotient 1 as the next digit in the result. 
Result so far: 28028.17391
If we subtract 23 from 30, we get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Step 12:
If we divide 70 by 23, we get 3 and a remainder of 1.
The next digit of our result is 3. 
Result so far: 28028.173913
Subtracting 69 from 70 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.

Advancing to step 13:
The number 23 fits into 10 0 times, leaving a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 28028.173913
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.

Moving on to step 14:
The number 23 fits into 100 4 times, leaving a remainder of 8.
Put 4 as the next digit of the answer. 
Result so far: 28028.17391304
The remainder is 8 after subtracting 92 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Our division results in 28028.17391304 with a remaining 8e-09.