64659560 ÷ 81 
The aim is to understand the frequency of 81 in 64659560.

Advancing to step 1:
The number 81 fits into 6 0 times, leaving a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Take the next digit (4) from the dividend and append it to 6, then repeat: 64 / 81

Let's proceed to step 2:
When dividing 64 by 81, we get 0 with a remainder of 64.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 64 to get 64.
Include the next digit (6) from the dividend after 64, then repeat: 646 / 81

Going ahead to step 3:
The number 81 fits into 646 7 times, leaving a remainder of 79.
Use 7 as the next digit of our solution. 
Result so far: 7.0
The remainder is 79 after subtracting 567 from 646.
Grab the next digit (5) from the dividend, add it to 79, then carry on: 795 / 81

Moving on to step 4:
If we divide 795 by 81, we get 9 and a remainder of 66.
The number 9 becomes the next digit in our result. 
Result so far: 79.0
Deduct 729 from 795 and we're left with 66.
Bring next digit (9) of the dividend behind the 66 and repeat the process: 669 / 81

Going ahead to step 5:
When dividing 669 by 81, we get 8 with a remainder of 21.
Write down 8 as next digit of the result. 
Result so far: 798.0
If we take 648 away from 669, we end up with 21.
Grab the next digit (5) from the dividend, add it to 21, then carry on: 215 / 81

On to step 6:
215 divided by 81 is 2 with a remainder of 53.
Use 2 as the next digit of our solution. 
Result so far: 7982.0
Deduct 162 from 215 and we're left with 53.
Take the next digit (6) from the dividend and append it to 53, then repeat: 536 / 81

Advancing to step 7:
81 goes into 536 6 times with a remainder of 50.
Write down 6 as next digit of the result. 
Result so far: 79826.0
If we take 486 away from 536, we end up with 50.
Take the next digit (0) from the dividend and append it to 50, then repeat: 500 / 81

Let's proceed to step 8:
When dividing 500 by 81, we get 6 with a remainder of 14.
Put 6 as the next digit of the answer. 
Result so far: 798266.0
Subtract 486 from 500 to get 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Moving on to step 9:
81 can be fit into 140 1 times, resulting in a remainder of 59.
Use 1 as the next digit of our solution. 
Result so far: 798266.1
The remainder is 59 after subtracting 81 from 140.
Since there are no more digits in the dividend, we add a zero to the remainder making it 590, and continue the process.

Going ahead to step 10:
81 goes into 590 7 times with a remainder of 23.
The number 7 becomes the next digit in our result. 
Result so far: 798266.17
Subtract 567 from 590 to get 23.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

On to step 11:
If we divide 230 by 81, we get 2 and a remainder of 68.
Use 2 as the next digit of our solution. 
Result so far: 798266.172
The remainder is 68 after subtracting 162 from 230.
Since there are no more digits in the dividend, we add a zero to the remainder making it 680, and continue the process.

Let's proceed to step 12:
When dividing 680 by 81, we get 8 with a remainder of 32.
Record the quotient 8 as the next digit in the result. 
Result so far: 798266.1728
Subtract 648 from 680 to get 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Advancing to step 13:
320 divided by 81 is 3 with a remainder of 77.
Put 3 as the next digit of the answer. 
Result so far: 798266.17283
If we take 243 away from 320, we end up with 77.
Since there are no more digits in the dividend, we add a zero to the remainder making it 770, and continue the process.

Going ahead to step 14:
770 divided by 81 is 9 with a remainder of 41.
Use 9 as the next digit of our solution. 
Result so far: 798266.172839
If we take 729 away from 770, we end up with 41.
Since there are no more digits in the dividend, we add a zero to the remainder making it 410, and continue the process.

Advancing to step 15:
If we divide 410 by 81, we get 5 and a remainder of 5.
The number 5 becomes the next digit in our result. 
Result so far: 798266.1728395
The remainder is 5 after subtracting 405 from 410.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 16:
When dividing 50 by 81, we get 0 with a remainder of 50.
The number 0 becomes the next digit in our result. 
Result so far: 798266.1728395
Subtract 0 from 50 to get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Our division results in 798266.1728395 with a remaining 5e-08.