669561 divided by 86 
The aim is to understand the frequency of 86 in 669561.

Step 1:
86 can be fit into 6 0 times, resulting in a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Append the next digit (6) from the dividend to 6 and continue with: 66 / 86

On to step 2:
When dividing 66 by 86, we get 0 with a remainder of 66.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 66 to get 66.
Fetch the next digit (9) from the dividend, attach it to 66 and continue: 669 / 86

Moving on to step 3:
If we divide 669 by 86, we get 7 and a remainder of 67.
Record the quotient 7 as the next digit in the result. 
Result so far: 7.0
Subtract 602 from 669 to get 67.
Append the next digit (5) from the dividend to 67 and continue with: 675 / 86

Moving on to step 4:
675 divided by 86 is 7 with a remainder of 73.
Record the quotient 7 as the next digit in the result. 
Result so far: 77.0
The remainder is 73 after subtracting 602 from 675.
Include the next digit (6) from the dividend after 73, then repeat: 736 / 86

Moving on to step 5:
736 divided by 86 is 8 with a remainder of 48.
The number 8 becomes the next digit in our result. 
Result so far: 778.0
Subtract 688 from 736 to get 48.
Fetch the next digit (1) from the dividend, attach it to 48 and continue: 481 / 86

Step 6:
481 divided by 86 is 5 with a remainder of 51.
Use 5 as the next digit of our solution. 
Result so far: 7785.0
Subtract 430 from 481 to get 51.
Since there are no more digits in the dividend, we add a zero to the remainder making it 510, and continue the process.

Step 7:
510 divided by 86 is 5 with a remainder of 80.
The number 5 becomes the next digit in our result. 
Result so far: 7785.5
The remainder is 80 after subtracting 430 from 510.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Let's proceed to step 8:
The number 86 fits into 800 9 times, leaving a remainder of 26.
Put 9 as the next digit of the answer. 
Result so far: 7785.59
Deduct 774 from 800 and we're left with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Advancing to step 9:
When dividing 260 by 86, we get 3 with a remainder of 2.
The number 3 becomes the next digit in our result. 
Result so far: 7785.593
The remainder is 2 after subtracting 258 from 260.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 10:
86 goes into 20 0 times with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 7785.593
Subtract 0 from 20 to 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.

Step 11:
The number 86 fits into 200 2 times, leaving a remainder of 28.
The number 2 becomes the next digit in our result. 
Result so far: 7785.59302
If we subtract 172 from 200, we get 28.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

Let's proceed to step 12:
When dividing 280 by 86, we get 3 with a remainder of 22.
Use 3 as the next digit of our solution. 
Result so far: 7785.593023
Deduct 258 from 280 and we're left with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Advancing to step 13:
When dividing 220 by 86, we get 2 with a remainder of 48.
The number 2 becomes the next digit in our result. 
Result so far: 7785.5930232
Subtracting 172 from 220 leaves us with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Let's proceed to step 14:
If we divide 480 by 86, we get 5 and a remainder of 50.
The number 5 becomes the next digit in our result. 
Result so far: 7785.59302325
If we subtract 430 from 480, we 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 7785.59302325 with a remaining 5e-08.