We look at the division of 20211668 by 135 
The aim is to understand the frequency of 135 in 20211668.

Advancing to step 1:
2 divided by 135 is 0 with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Bring next digit (0) of the dividend behind the 2 and repeat the process: 20 / 135

Moving on to step 2:
135 goes into 20 0 times with a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 20, we end up with 20.
Grab the next digit (2) from the dividend, add it to 20, then carry on: 202 / 135

Advancing to step 3:
202 divided by 135 is 1 with a remainder of 67.
The next digit of our result is 1. 
Result so far: 1.0
If we subtract 135 from 202, we get 67.
Take the next digit (1) from the dividend and append it to 67, then repeat: 671 / 135

Let's proceed to step 4:
If we divide 671 by 135, we get 4 and a remainder of 131.
Write down 4 as next digit of the result. 
Result so far: 14.0
Subtracting 540 from 671 leaves us with 131.
Append the next digit (1) from the dividend to 131 and continue with: 1311 / 135

Let's proceed to step 5:
When dividing 1311 by 135, we get 9 with a remainder of 96.
Use 9 as the next digit of our solution. 
Result so far: 149.0
If we subtract 1215 from 1311, we get 96.
Grab the next digit (6) from the dividend, add it to 96, then carry on: 966 / 135

Moving on to step 6:
If we divide 966 by 135, we get 7 and a remainder of 21.
Put 7 as the next digit of the answer. 
Result so far: 1497.0
Subtracting 945 from 966 leaves us with 21.
Grab the next digit (6) from the dividend, add it to 21, then carry on: 216 / 135

Moving on to step 7:
135 goes into 216 1 times with a remainder of 81.
Record the quotient 1 as the next digit in the result. 
Result so far: 14971.0
Deduct 135 from 216 and we're left with 81.
Take the next digit (8) from the dividend and append it to 81, then repeat: 818 / 135

Going ahead to step 8:
If we divide 818 by 135, we get 6 and a remainder of 8.
Put 6 as the next digit of the answer. 
Result so far: 149716.0
Subtract 810 from 818 to get 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:
If we divide 80 by 135, we get 0 and a remainder of 80.
Use 0 as the next digit of our solution. 
Result so far: 149716.0
Subtract 0 from 80 to get 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Advancing to step 10:
800 divided by 135 is 5 with a remainder of 125.
The number 5 becomes the next digit in our result. 
Result so far: 149716.05
If we subtract 675 from 800, we get 125.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1250, and continue the process.

Step 11:
135 goes into 1250 9 times with a remainder of 35.
Use 9 as the next digit of our solution. 
Result so far: 149716.059
Subtract 1215 from 1250 to get 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

On to step 12:
350 divided by 135 is 2 with a remainder of 80.
Put 2 as the next digit of the answer. 
Result so far: 149716.0592
If we take 270 away from 350, we end up with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Advancing to step 13:
The number 135 fits into 800 5 times, leaving a remainder of 125.
The next digit of our result is 5. 
Result so far: 149716.05925
If we subtract 675 from 800, we get 125.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1250, and continue the process.

Let's proceed to step 14:
If we divide 1250 by 135, we get 9 and a remainder of 35.
The next digit of our result is 9. 
Result so far: 149716.059259
Subtract 1215 from 1250 to get 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

Going ahead to step 15:
135 goes into 350 2 times with a remainder of 80.
The next digit of our result is 2. 
Result so far: 149716.0592592
Deduct 270 from 350 and we're left with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Moving on to step 16:
The number 135 fits into 800 5 times, leaving a remainder of 125.
The number 5 becomes the next digit in our result. 
Result so far: 149716.05925925
Deduct 675 from 800 and we're left with 125.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1250, and continue the process.

The final result is 149716.05925925 with a remainder of 1.25e-07.