We're dividing 63615658 by 66 
The aim is to understand the frequency of 66 in 63615658.

On to step 1:
If we divide 6 by 66, we get 0 and a remainder of 6.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Grab the next digit (3) from the dividend, add it to 6, then carry on: 63 / 66

Moving on to step 2:
If we divide 63 by 66, we get 0 and a remainder of 63.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 63 after subtracting 0 from 63.
Fetch the next digit (6) from the dividend, attach it to 63 and continue: 636 / 66

Going ahead to step 3:
66 goes into 636 9 times with a remainder of 42.
Put 9 as the next digit of the answer. 
Result so far: 9.0
If we take 594 away from 636, we end up with 42.
Include the next digit (1) from the dividend after 42, then repeat: 421 / 66

On to step 4:
66 goes into 421 6 times with a remainder of 25.
Use 6 as the next digit of our solution. 
Result so far: 96.0
Subtracting 396 from 421 leaves us with 25.
Grab the next digit (5) from the dividend, add it to 25, then carry on: 255 / 66

Moving on to step 5:
If we divide 255 by 66, we get 3 and a remainder of 57.
Record the quotient 3 as the next digit in the result. 
Result so far: 963.0
Subtracting 198 from 255 leaves us with 57.
Include the next digit (6) from the dividend after 57, then repeat: 576 / 66

Going ahead to step 6:
If we divide 576 by 66, we get 8 and a remainder of 48.
The next digit of our result is 8. 
Result so far: 9638.0
If we take 528 away from 576, we end up with 48.
Include the next digit (5) from the dividend after 48, then repeat: 485 / 66

On to step 7:
66 goes into 485 7 times with a remainder of 23.
Write down 7 as next digit of the result. 
Result so far: 96387.0
If we take 462 away from 485, we end up with 23.
Include the next digit (8) from the dividend after 23, then repeat: 238 / 66

On to step 8:
If we divide 238 by 66, we get 3 and a remainder of 40.
Use 3 as the next digit of our solution. 
Result so far: 963873.0
The remainder is 40 after subtracting 198 from 238.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

On to step 9:
400 divided by 66 is 6 with a remainder of 4.
Put 6 as the next digit of the answer. 
Result so far: 963873.6
The remainder is 4 after subtracting 396 from 400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Step 10:
66 goes into 40 0 times with a remainder of 40.
Write down 0 as next digit of the result. 
Result so far: 963873.6
Subtracting 0 from 40 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Moving on to step 11:
If we divide 400 by 66, we get 6 and a remainder of 4.
Put 6 as the next digit of the answer. 
Result so far: 963873.606
Subtract 396 from 400 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Going ahead to step 12:
66 can be fit into 40 0 times, resulting in a remainder of 40.
The number 0 becomes the next digit in our result. 
Result so far: 963873.606
If we subtract 0 from 40, we get 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Moving on to step 13:
66 can be fit into 400 6 times, resulting in a remainder of 4.
Write down 6 as next digit of the result. 
Result so far: 963873.60606
Deduct 396 from 400 and we're left with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 14:
When dividing 40 by 66, we get 0 with a remainder of 40.
Use 0 as the next digit of our solution. 
Result so far: 963873.60606
Subtracting 0 from 40 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Going ahead to step 15:
400 divided by 66 is 6 with a remainder of 4.
Use 6 as the next digit of our solution. 
Result so far: 963873.6060606
Deduct 396 from 400 and we're left with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Let's proceed to step 16:
If we divide 40 by 66, we get 0 and a remainder of 40.
The next digit of our result is 0. 
Result so far: 963873.6060606
The remainder is 40 after subtracting 0 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

In conclusion, the division gives 963873.6060606 with a balance of 4e-08.