805691 divided by 81 
The aim is to understand the frequency of 81 in 805691.

On to step 1:
The number 81 fits into 8 0 times, leaving a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Fetch the next digit (0) from the dividend, attach it to 8 and continue: 80 / 81

On to step 2:
When dividing 80 by 81, we get 0 with a remainder of 80.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 80 after subtracting 0 from 80.
Include the next digit (5) from the dividend after 80, then repeat: 805 / 81

Going ahead to step 3:
If we divide 805 by 81, we get 9 and a remainder of 76.
The number 9 becomes the next digit in our result. 
Result so far: 9.0
The remainder is 76 after subtracting 729 from 805.
Fetch the next digit (6) from the dividend, attach it to 76 and continue: 766 / 81

Advancing to step 4:
81 goes into 766 9 times with a remainder of 37.
Record the quotient 9 as the next digit in the result. 
Result so far: 99.0
Deduct 729 from 766 and we're left with 37.
Grab the next digit (9) from the dividend, add it to 37, then carry on: 379 / 81

Moving on to step 5:
When dividing 379 by 81, we get 4 with a remainder of 55.
Write down 4 as next digit of the result. 
Result so far: 994.0
If we subtract 324 from 379, we get 55.
Append the next digit (1) from the dividend to 55 and continue with: 551 / 81

Moving on to step 6:
If we divide 551 by 81, we get 6 and a remainder of 65.
Put 6 as the next digit of the answer. 
Result so far: 9946.0
If we subtract 486 from 551, we get 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

On to step 7:
When dividing 650 by 81, we get 8 with a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 9946.8
Deduct 648 from 650 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 8:
When dividing 20 by 81, we get 0 with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 9946.8
If we subtract 0 from 20, we get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 9:
If we divide 200 by 81, we get 2 and a remainder of 38.
Use 2 as the next digit of our solution. 
Result so far: 9946.802
Subtract 162 from 200 to get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Let's proceed to step 10:
When dividing 380 by 81, we get 4 with a remainder of 56.
The next digit of our result is 4. 
Result so far: 9946.8024
Deduct 324 from 380 and we're left with 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Step 11:
81 can be fit into 560 6 times, resulting in a remainder of 74.
Use 6 as the next digit of our solution. 
Result so far: 9946.80246
The remainder is 74 after subtracting 486 from 560.
Since there are no more digits in the dividend, we add a zero to the remainder making it 740, and continue the process.

Going ahead to step 12:
81 can be fit into 740 9 times, resulting in a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 9946.802469
If we take 729 away from 740, we end up 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.

Moving on to step 13:
The number 81 fits into 110 1 times, leaving a remainder of 29.
The next digit of our result is 1. 
Result so far: 9946.8024691
The remainder is 29 after subtracting 81 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Advancing to step 14:
The number 81 fits into 290 3 times, leaving a remainder of 47.
The next digit of our result is 3. 
Result so far: 9946.80246913
If we subtract 243 from 290, we get 47.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

Our division results in 9946.80246913 with a remaining 4.7e-08.