We divide 538157 by 21
The aim is to understand the frequency of 21 in 538157.

Step 1:
When dividing 5 by 21, we get 0 with a remainder of 5.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 5 to get 5.
Include the next digit (3) from the dividend after 5, then repeat: 53 / 21

Let's proceed to step 2:
When dividing 53 by 21, we get 2 with a remainder of 11.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
If we subtract 42 from 53, we get 11.
Bring next digit (8) of the dividend behind the 11 and repeat the process: 118 / 21

On to step 3:
If we divide 118 by 21, we get 5 and a remainder of 13.
Write down 5 as next digit of the result. 
Result so far: 25.0
Subtracting 105 from 118 leaves us with 13.
Fetch the next digit (1) from the dividend, attach it to 13 and continue: 131 / 21

Going ahead to step 4:
If we divide 131 by 21, we get 6 and a remainder of 5.
Use 6 as the next digit of our solution. 
Result so far: 256.0
Subtract 126 from 131 to get 5.
Grab the next digit (5) from the dividend, add it to 5, then carry on: 55 / 21

Advancing to step 5:
21 can be fit into 55 2 times, resulting in a remainder of 13.
Use 2 as the next digit of our solution. 
Result so far: 2562.0
Subtracting 42 from 55 leaves us with 13.
Grab the next digit (7) from the dividend, add it to 13, then carry on: 137 / 21

On to step 6:
21 can be fit into 137 6 times, resulting in a remainder of 11.
Write down 6 as next digit of the result. 
Result so far: 25626.0
Subtracting 126 from 137 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.

Let's proceed to step 7:
When dividing 110 by 21, we get 5 with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 25626.5
The remainder is 5 after subtracting 105 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Let's proceed to step 8:
If we divide 50 by 21, we get 2 and a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 25626.52
Subtracting 42 from 50 leaves us 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.

Let's proceed to step 9:
21 goes into 80 3 times with a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 25626.523
If we take 63 away from 80, we end up with 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 10:
The number 21 fits into 170 8 times, leaving a remainder of 2.
Put 8 as the next digit of the answer. 
Result so far: 25626.5238
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 11:
20 divided by 21 is 0 with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 25626.5238
Subtracting 0 from 20 leaves us 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.

Going ahead to step 12:
200 divided by 21 is 9 with a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 25626.523809
The remainder is 11 after subtracting 189 from 200.
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 13:
The number 21 fits into 110 5 times, leaving a remainder of 5.
The next digit of our result is 5. 
Result so far: 25626.5238095
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.

Let's proceed to step 14:
21 goes into 50 2 times with a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 25626.52380952
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.

After the division, we end up with 25626.52380952 and a remainder of 8e-09.