13570927 divided by 81 
The aim is to understand the frequency of 81 in 13570927.

Let's proceed to step 1:
When dividing 1 by 81, we get 0 with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 81

Going ahead to step 2:
When dividing 13 by 81, we get 0 with a remainder of 13.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 13, we end up with 13.
Take the next digit (5) from the dividend and append it to 13, then repeat: 135 / 81

Going ahead to step 3:
The number 81 fits into 135 1 times, leaving a remainder of 54.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Deduct 81 from 135 and we're left with 54.
Grab the next digit (7) from the dividend, add it to 54, then carry on: 547 / 81

Going ahead to step 4:
81 can be fit into 547 6 times, resulting in a remainder of 61.
Write down 6 as next digit of the result. 
Result so far: 16.0
If we subtract 486 from 547, we get 61.
Append the next digit (0) from the dividend to 61 and continue with: 610 / 81

On to step 5:
81 can be fit into 610 7 times, resulting in a remainder of 43.
Write down 7 as next digit of the result. 
Result so far: 167.0
The remainder is 43 after subtracting 567 from 610.
Append the next digit (9) from the dividend to 43 and continue with: 439 / 81

Step 6:
81 goes into 439 5 times with a remainder of 34.
Use 5 as the next digit of our solution. 
Result so far: 1675.0
If we take 405 away from 439, we end up with 34.
Grab the next digit (2) from the dividend, add it to 34, then carry on: 342 / 81

Moving on to step 7:
342 divided by 81 is 4 with a remainder of 18.
The number 4 becomes the next digit in our result. 
Result so far: 16754.0
Subtracting 324 from 342 leaves us with 18.
Bring next digit (7) of the dividend behind the 18 and repeat the process: 187 / 81

Going ahead to step 8:
81 goes into 187 2 times with a remainder of 25.
Record the quotient 2 as the next digit in the result. 
Result so far: 167542.0
Deduct 162 from 187 and we're left with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

On to step 9:
The number 81 fits into 250 3 times, leaving a remainder of 7.
The next digit of our result is 3. 
Result so far: 167542.3
Deduct 243 from 250 and we're left with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

On to step 10:
81 goes into 70 0 times with a remainder of 70.
Put 0 as the next digit of the answer. 
Result so far: 167542.3
If we take 0 away from 70, we end up with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Step 11:
The number 81 fits into 700 8 times, leaving a remainder of 52.
Use 8 as the next digit of our solution. 
Result so far: 167542.308
If we take 648 away from 700, we end up with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Going ahead to step 12:
The number 81 fits into 520 6 times, leaving a remainder of 34.
The number 6 becomes the next digit in our result. 
Result so far: 167542.3086
Subtract 486 from 520 to get 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Advancing to step 13:
The number 81 fits into 340 4 times, leaving a remainder of 16.
Use 4 as the next digit of our solution. 
Result so far: 167542.30864
Subtracting 324 from 340 leaves us 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.

Let's proceed to step 14:
160 divided by 81 is 1 with a remainder of 79.
Use 1 as the next digit of our solution. 
Result so far: 167542.308641
If we take 81 away from 160, we end up with 79.
Since there are no more digits in the dividend, we add a zero to the remainder making it 790, and continue the process.

Let's proceed to step 15:
The number 81 fits into 790 9 times, leaving a remainder of 61.
The next digit of our result is 9. 
Result so far: 167542.3086419
If we take 729 away from 790, we end up with 61.
Since there are no more digits in the dividend, we add a zero to the remainder making it 610, and continue the process.

Step 16:
When dividing 610 by 81, we get 7 with a remainder of 43.
The next digit of our result is 7. 
Result so far: 167542.30864197
Subtract 567 from 610 to get 43.
Since there are no more digits in the dividend, we add a zero to the remainder making it 430, and continue the process.

The final result is 167542.30864197 with a remainder of 4.3e-08.