We divide 271572 by 21
The aim is to understand the frequency of 21 in 271572.

Let's proceed to step 1:
2 divided by 21 is 0 with a remainder of 2.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Append the next digit (7) from the dividend to 2 and continue with: 27 / 21

Step 2:
21 can be fit into 27 1 times, resulting in a remainder of 6.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtracting 21 from 27 leaves us with 6.
Include the next digit (1) from the dividend after 6, then repeat: 61 / 21

Advancing to step 3:
When dividing 61 by 21, we get 2 with a remainder of 19.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
Subtracting 42 from 61 leaves us with 19.
Fetch the next digit (5) from the dividend, attach it to 19 and continue: 195 / 21

Advancing to step 4:
21 goes into 195 9 times with a remainder of 6.
Record the quotient 9 as the next digit in the result. 
Result so far: 129.0
If we take 189 away from 195, we end up with 6.
Fetch the next digit (7) from the dividend, attach it to 6 and continue: 67 / 21

On to step 5:
21 can be fit into 67 3 times, resulting in a remainder of 4.
The next digit of our result is 3. 
Result so far: 1293.0
If we take 63 away from 67, we end up with 4.
Bring next digit (2) of the dividend behind the 4 and repeat the process: 42 / 21

Advancing to step 6:
The number 21 fits into 42 2 times, leaving a remainder of 0.
The next digit of our result is 2. 
Result so far: 12932.0
If we subtract 42 from 42, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 7:
21 can be fit into 0 0 times, resulting in a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 12932.0
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 8:
21 can be fit into 0 0 times, resulting in a remainder of 0.
The next digit of our result is 0. 
Result so far: 12932.0
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Our division results in 12932.0 with a remaining 0.0.