86720636 ÷ 405 
The aim is to understand the frequency of 405 in 86720636.

Step 1:
405 can be fit into 8 0 times, resulting in a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Append the next digit (6) from the dividend to 8 and continue with: 86 / 405

Advancing to step 2:
86 divided by 405 is 0 with a remainder of 86.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 86, we end up with 86.
Append the next digit (7) from the dividend to 86 and continue with: 867 / 405

Moving on to step 3:
When dividing 867 by 405, we get 2 with a remainder of 57.
Use 2 as the next digit of our solution. 
Result so far: 2.0
Subtracting 810 from 867 leaves us with 57.
Take the next digit (2) from the dividend and append it to 57, then repeat: 572 / 405

Let's proceed to step 4:
If we divide 572 by 405, we get 1 and a remainder of 167.
The number 1 becomes the next digit in our result. 
Result so far: 21.0
Subtracting 405 from 572 leaves us with 167.
Grab the next digit (0) from the dividend, add it to 167, then carry on: 1670 / 405

Advancing to step 5:
405 goes into 1670 4 times with a remainder of 50.
Record the quotient 4 as the next digit in the result. 
Result so far: 214.0
If we take 1620 away from 1670, we end up with 50.
Grab the next digit (6) from the dividend, add it to 50, then carry on: 506 / 405

On to step 6:
When dividing 506 by 405, we get 1 with a remainder of 101.
Put 1 as the next digit of the answer. 
Result so far: 2141.0
If we subtract 405 from 506, we get 101.
Include the next digit (3) from the dividend after 101, then repeat: 1013 / 405

Let's proceed to step 7:
The number 405 fits into 1013 2 times, leaving a remainder of 203.
Put 2 as the next digit of the answer. 
Result so far: 21412.0
If we subtract 810 from 1013, we get 203.
Include the next digit (6) from the dividend after 203, then repeat: 2036 / 405

Step 8:
405 can be fit into 2036 5 times, resulting in a remainder of 11.
Use 5 as the next digit of our solution. 
Result so far: 214125.0
Subtracting 2025 from 2036 leaves us with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Going ahead to step 9:
405 can be fit into 110 0 times, resulting in a remainder of 110.
The next digit of our result is 0. 
Result so far: 214125.0
Deduct 0 from 110 and we're left with 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1100, and continue the process.

On to step 10:
When dividing 1100 by 405, we get 2 with a remainder of 290.
The number 2 becomes the next digit in our result. 
Result so far: 214125.02
If we take 810 away from 1100, we end up with 290.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2900, and continue the process.

Let's proceed to step 11:
405 can be fit into 2900 7 times, resulting in a remainder of 65.
Put 7 as the next digit of the answer. 
Result so far: 214125.027
If we take 2835 away from 2900, we end up with 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Advancing to step 12:
650 divided by 405 is 1 with a remainder of 245.
Record the quotient 1 as the next digit in the result. 
Result so far: 214125.0271
Deduct 405 from 650 and we're left with 245.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2450, and continue the process.

On to step 13:
405 goes into 2450 6 times with a remainder of 20.
Write down 6 as next digit of the result. 
Result so far: 214125.02716
The remainder is 20 after subtracting 2430 from 2450.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Moving on to step 14:
The number 405 fits into 200 0 times, leaving a remainder of 200.
Use 0 as the next digit of our solution. 
Result so far: 214125.02716
If we take 0 away from 200, we end up with 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2000, and continue the process.

On to step 15:
When dividing 2000 by 405, we get 4 with a remainder of 380.
The next digit of our result is 4. 
Result so far: 214125.0271604
If we subtract 1620 from 2000, we get 380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3800, and continue the process.

Advancing to step 16:
405 goes into 3800 9 times with a remainder of 155.
Write down 9 as next digit of the result. 
Result so far: 214125.02716049
If we subtract 3645 from 3800, we get 155.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1550, and continue the process.

The quotient of the division is 214125.02716049, and the remainder is 1.55e-07.