Let's divide 13289648 by 645
The aim is to understand the frequency of 645 in 13289648.

Step 1:
645 goes into 1 0 times with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Append the next digit (3) from the dividend to 1 and continue with: 13 / 645

Going ahead to step 2:
13 divided by 645 is 0 with a remainder of 13.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 13 and we're left with 13.
Grab the next digit (2) from the dividend, add it to 13, then carry on: 132 / 645

Advancing to step 3:
132 divided by 645 is 0 with a remainder of 132.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 132 to get 132.
Fetch the next digit (8) from the dividend, attach it to 132 and continue: 1328 / 645

Advancing to step 4:
645 can be fit into 1328 2 times, resulting in a remainder of 38.
The next digit of our result is 2. 
Result so far: 2.0
Subtracting 1290 from 1328 leaves us with 38.
Fetch the next digit (9) from the dividend, attach it to 38 and continue: 389 / 645

Step 5:
645 goes into 389 0 times with a remainder of 389.
Write down 0 as next digit of the result. 
Result so far: 20.0
Subtracting 0 from 389 leaves us with 389.
Grab the next digit (6) from the dividend, add it to 389, then carry on: 3896 / 645

On to step 6:
When dividing 3896 by 645, we get 6 with a remainder of 26.
Use 6 as the next digit of our solution. 
Result so far: 206.0
Subtracting 3870 from 3896 leaves us with 26.
Include the next digit (4) from the dividend after 26, then repeat: 264 / 645

Moving on to step 7:
The number 645 fits into 264 0 times, leaving a remainder of 264.
Use 0 as the next digit of our solution. 
Result so far: 2060.0
Subtract 0 from 264 to get 264.
Fetch the next digit (8) from the dividend, attach it to 264 and continue: 2648 / 645

On to step 8:
When dividing 2648 by 645, we get 4 with a remainder of 68.
Use 4 as the next digit of our solution. 
Result so far: 20604.0
Deduct 2580 from 2648 and we're left with 68.
Since there are no more digits in the dividend, we add a zero to the remainder making it 680, and continue the process.

Going ahead to step 9:
680 divided by 645 is 1 with a remainder of 35.
The number 1 becomes the next digit in our result. 
Result so far: 20604.1
The remainder is 35 after subtracting 645 from 680.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

Let's proceed to step 10:
When dividing 350 by 645, we get 0 with a remainder of 350.
Write down 0 as next digit of the result. 
Result so far: 20604.1
Subtract 0 from 350 to get 350.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3500, and continue the process.

Going ahead to step 11:
When dividing 3500 by 645, we get 5 with a remainder of 275.
The next digit of our result is 5. 
Result so far: 20604.105
Deduct 3225 from 3500 and we're left with 275.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2750, and continue the process.

On to step 12:
645 can be fit into 2750 4 times, resulting in a remainder of 170.
The next digit of our result is 4. 
Result so far: 20604.1054
Subtracting 2580 from 2750 leaves us with 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1700, and continue the process.

Step 13:
1700 divided by 645 is 2 with a remainder of 410.
Use 2 as the next digit of our solution. 
Result so far: 20604.10542
If we take 1290 away from 1700, we end up with 410.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4100, and continue the process.

Going ahead to step 14:
4100 divided by 645 is 6 with a remainder of 230.
The number 6 becomes the next digit in our result. 
Result so far: 20604.105426
The remainder is 230 after subtracting 3870 from 4100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2300, and continue the process.

Going ahead to step 15:
645 goes into 2300 3 times with a remainder of 365.
The number 3 becomes the next digit in our result. 
Result so far: 20604.1054263
If we take 1935 away from 2300, we end up with 365.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3650, and continue the process.

Step 16:
3650 divided by 645 is 5 with a remainder of 425.
Record the quotient 5 as the next digit in the result. 
Result so far: 20604.10542635
Subtracting 3225 from 3650 leaves us with 425.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4250, and continue the process.

In conclusion, the division gives 20604.10542635 with a balance of 4.25e-07.