We look at the division of 36636043 by 405 
The aim is to understand the frequency of 405 in 36636043.

Going ahead to step 1:
3 divided by 405 is 0 with a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 3 and we're left with 3.
Fetch the next digit (6) from the dividend, attach it to 3 and continue: 36 / 405

On to step 2:
If we divide 36 by 405, we get 0 and a remainder of 36.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 36 leaves us with 36.
Bring next digit (6) of the dividend behind the 36 and repeat the process: 366 / 405

Step 3:
The number 405 fits into 366 0 times, leaving a remainder of 366.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 366 leaves us with 366.
Include the next digit (3) from the dividend after 366, then repeat: 3663 / 405

Let's proceed to step 4:
The number 405 fits into 3663 9 times, leaving a remainder of 18.
The number 9 becomes the next digit in our result. 
Result so far: 9.0
If we subtract 3645 from 3663, we get 18.
Take the next digit (6) from the dividend and append it to 18, then repeat: 186 / 405

Going ahead to step 5:
If we divide 186 by 405, we get 0 and a remainder of 186.
The number 0 becomes the next digit in our result. 
Result so far: 90.0
If we subtract 0 from 186, we get 186.
Include the next digit (0) from the dividend after 186, then repeat: 1860 / 405

On to step 6:
1860 divided by 405 is 4 with a remainder of 240.
Use 4 as the next digit of our solution. 
Result so far: 904.0
If we subtract 1620 from 1860, we get 240.
Take the next digit (4) from the dividend and append it to 240, then repeat: 2404 / 405

Step 7:
405 can be fit into 2404 5 times, resulting in a remainder of 379.
The next digit of our result is 5. 
Result so far: 9045.0
Deduct 2025 from 2404 and we're left with 379.
Bring next digit (3) of the dividend behind the 379 and repeat the process: 3793 / 405

Let's proceed to step 8:
3793 divided by 405 is 9 with a remainder of 148.
The next digit of our result is 9. 
Result so far: 90459.0
If we subtract 3645 from 3793, we get 148.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1480, and continue the process.

Moving on to step 9:
405 goes into 1480 3 times with a remainder of 265.
The next digit of our result is 3. 
Result so far: 90459.3
If we subtract 1215 from 1480, we get 265.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2650, and continue the process.

Going ahead to step 10:
405 goes into 2650 6 times with a remainder of 220.
The number 6 becomes the next digit in our result. 
Result so far: 90459.36
The remainder is 220 after subtracting 2430 from 2650.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2200, and continue the process.

Step 11:
2200 divided by 405 is 5 with a remainder of 175.
Record the quotient 5 as the next digit in the result. 
Result so far: 90459.365
The remainder is 175 after subtracting 2025 from 2200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1750, and continue the process.

Step 12:
When dividing 1750 by 405, we get 4 with a remainder of 130.
The next digit of our result is 4. 
Result so far: 90459.3654
The remainder is 130 after subtracting 1620 from 1750.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1300, and continue the process.

Advancing to step 13:
The number 405 fits into 1300 3 times, leaving a remainder of 85.
Record the quotient 3 as the next digit in the result. 
Result so far: 90459.36543
Deduct 1215 from 1300 and we're left with 85.
Since there are no more digits in the dividend, we add a zero to the remainder making it 850, and continue the process.

Advancing to step 14:
The number 405 fits into 850 2 times, leaving a remainder of 40.
The number 2 becomes the next digit in our result. 
Result so far: 90459.365432
If we take 810 away from 850, we end up 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.

Let's proceed to step 15:
If we divide 400 by 405, we get 0 and a remainder of 400.
Write down 0 as next digit of the result. 
Result so far: 90459.365432
If we take 0 away from 400, we end up with 400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4000, and continue the process.

Going ahead to step 16:
If we divide 4000 by 405, we get 9 and a remainder of 355.
The next digit of our result is 9. 
Result so far: 90459.36543209
Deduct 3645 from 4000 and we're left with 355.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3550, and continue the process.

After the division, we end up with 90459.36543209 and a remainder of 3.55e-07.