We look at the division of 64677435 by 409 
The aim is to understand the frequency of 409 in 64677435.

Moving on to step 1:
If we divide 6 by 409, we get 0 and a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Fetch the next digit (4) from the dividend, attach it to 6 and continue: 64 / 409

Let's proceed to step 2:
409 goes into 64 0 times with a remainder of 64.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 64 after subtracting 0 from 64.
Include the next digit (6) from the dividend after 64, then repeat: 646 / 409

Going ahead to step 3:
If we divide 646 by 409, we get 1 and a remainder of 237.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Subtracting 409 from 646 leaves us with 237.
Append the next digit (7) from the dividend to 237 and continue with: 2377 / 409

On to step 4:
2377 divided by 409 is 5 with a remainder of 332.
Use 5 as the next digit of our solution. 
Result so far: 15.0
If we subtract 2045 from 2377, we get 332.
Grab the next digit (7) from the dividend, add it to 332, then carry on: 3327 / 409

Moving on to step 5:
When dividing 3327 by 409, we get 8 with a remainder of 55.
Put 8 as the next digit of the answer. 
Result so far: 158.0
Deduct 3272 from 3327 and we're left with 55.
Include the next digit (4) from the dividend after 55, then repeat: 554 / 409

Going ahead to step 6:
409 can be fit into 554 1 times, resulting in a remainder of 145.
Record the quotient 1 as the next digit in the result. 
Result so far: 1581.0
The remainder is 145 after subtracting 409 from 554.
Grab the next digit (3) from the dividend, add it to 145, then carry on: 1453 / 409

Step 7:
When dividing 1453 by 409, we get 3 with a remainder of 226.
The number 3 becomes the next digit in our result. 
Result so far: 15813.0
Subtract 1227 from 1453 to get 226.
Grab the next digit (5) from the dividend, add it to 226, then carry on: 2265 / 409

Moving on to step 8:
409 goes into 2265 5 times with a remainder of 220.
Record the quotient 5 as the next digit in the result. 
Result so far: 158135.0
Deduct 2045 from 2265 and we're left with 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2200, and continue the process.

Going ahead to step 9:
When dividing 2200 by 409, we get 5 with a remainder of 155.
Use 5 as the next digit of our solution. 
Result so far: 158135.5
If we subtract 2045 from 2200, 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.

Let's proceed to step 10:
If we divide 1550 by 409, we get 3 and a remainder of 323.
Write down 3 as next digit of the result. 
Result so far: 158135.53
Subtracting 1227 from 1550 leaves us with 323.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3230, and continue the process.

Advancing to step 11:
3230 divided by 409 is 7 with a remainder of 367.
Write down 7 as next digit of the result. 
Result so far: 158135.537
The remainder is 367 after subtracting 2863 from 3230.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3670, and continue the process.

Going ahead to step 12:
409 goes into 3670 8 times with a remainder of 398.
Put 8 as the next digit of the answer. 
Result so far: 158135.5378
If we subtract 3272 from 3670, we get 398.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3980, and continue the process.

On to step 13:
409 can be fit into 3980 9 times, resulting in a remainder of 299.
The number 9 becomes the next digit in our result. 
Result so far: 158135.53789
If we subtract 3681 from 3980, we get 299.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2990, and continue the process.

Going ahead to step 14:
2990 divided by 409 is 7 with a remainder of 127.
The next digit of our result is 7. 
Result so far: 158135.537897
If we take 2863 away from 2990, we end up with 127.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1270, and continue the process.

Step 15:
409 can be fit into 1270 3 times, resulting in a remainder of 43.
The next digit of our result is 3. 
Result so far: 158135.5378973
The remainder is 43 after subtracting 1227 from 1270.
Since there are no more digits in the dividend, we add a zero to the remainder making it 430, and continue the process.

Going ahead to step 16:
When dividing 430 by 409, we get 1 with a remainder of 21.
Record the quotient 1 as the next digit in the result. 
Result so far: 158135.53789731
If we take 409 away from 430, we end up with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

The final outcome is 158135.53789731, with a leftover of 2.1e-08.