13617501 divided by 561 
The aim is to understand the frequency of 561 in 13617501.

Step 1:
When dividing 1 by 561, we get 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Include the next digit (3) from the dividend after 1, then repeat: 13 / 561

Moving on to step 2:
13 divided by 561 is 0 with a remainder of 13.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 13 leaves us with 13.
Include the next digit (6) from the dividend after 13, then repeat: 136 / 561

Step 3:
136 divided by 561 is 0 with a remainder of 136.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 136 to get 136.
Include the next digit (1) from the dividend after 136, then repeat: 1361 / 561

Advancing to step 4:
When dividing 1361 by 561, we get 2 with a remainder of 239.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
The remainder is 239 after subtracting 1122 from 1361.
Append the next digit (7) from the dividend to 239 and continue with: 2397 / 561

On to step 5:
When dividing 2397 by 561, we get 4 with a remainder of 153.
Use 4 as the next digit of our solution. 
Result so far: 24.0
Deduct 2244 from 2397 and we're left with 153.
Include the next digit (5) from the dividend after 153, then repeat: 1535 / 561

Going ahead to step 6:
If we divide 1535 by 561, we get 2 and a remainder of 413.
Record the quotient 2 as the next digit in the result. 
Result so far: 242.0
Deduct 1122 from 1535 and we're left with 413.
Grab the next digit (0) from the dividend, add it to 413, then carry on: 4130 / 561

Let's proceed to step 7:
When dividing 4130 by 561, we get 7 with a remainder of 203.
Put 7 as the next digit of the answer. 
Result so far: 2427.0
Subtracting 3927 from 4130 leaves us with 203.
Take the next digit (1) from the dividend and append it to 203, then repeat: 2031 / 561

Let's proceed to step 8:
The number 561 fits into 2031 3 times, leaving a remainder of 348.
The next digit of our result is 3. 
Result so far: 24273.0
Subtract 1683 from 2031 to get 348.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3480, and continue the process.

Step 9:
3480 divided by 561 is 6 with a remainder of 114.
Put 6 as the next digit of the answer. 
Result so far: 24273.6
Deduct 3366 from 3480 and we're left with 114.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1140, and continue the process.

Step 10:
If we divide 1140 by 561, we get 2 and a remainder of 18.
The next digit of our result is 2. 
Result so far: 24273.62
Subtracting 1122 from 1140 leaves us with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Let's proceed to step 11:
180 divided by 561 is 0 with a remainder of 180.
Use 0 as the next digit of our solution. 
Result so far: 24273.62
If we take 0 away from 180, we end up with 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1800, and continue the process.

Let's proceed to step 12:
561 can be fit into 1800 3 times, resulting in a remainder of 117.
The next digit of our result is 3. 
Result so far: 24273.6203
Subtracting 1683 from 1800 leaves us with 117.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1170, and continue the process.

Going ahead to step 13:
1170 divided by 561 is 2 with a remainder of 48.
Put 2 as the next digit of the answer. 
Result so far: 24273.62032
If we subtract 1122 from 1170, we get 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Advancing to step 14:
When dividing 480 by 561, we get 0 with a remainder of 480.
The number 0 becomes the next digit in our result. 
Result so far: 24273.62032
Deduct 0 from 480 and we're left with 480.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4800, and continue the process.

Moving on to step 15:
If we divide 4800 by 561, we get 8 and a remainder of 312.
Write down 8 as next digit of the result. 
Result so far: 24273.6203208
If we subtract 4488 from 4800, we get 312.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3120, and continue the process.

Moving on to step 16:
If we divide 3120 by 561, we get 5 and a remainder of 315.
Put 5 as the next digit of the answer. 
Result so far: 24273.62032085
If we subtract 2805 from 3120, we get 315.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3150, and continue the process.

After the division, we end up with 24273.62032085 and a remainder of 3.15e-07.