We're dividing 18637329 by 321 
The aim is to understand the frequency of 321 in 18637329.

Let's proceed to step 1:
When dividing 1 by 321, 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 (8) from the dividend after 1, then repeat: 18 / 321

Going ahead to step 2:
When dividing 18 by 321, we get 0 with a remainder of 18.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 18 and we're left with 18.
Append the next digit (6) from the dividend to 18 and continue with: 186 / 321

Let's proceed to step 3:
186 divided by 321 is 0 with a remainder of 186.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 186 to get 186.
Grab the next digit (3) from the dividend, add it to 186, then carry on: 1863 / 321

Moving on to step 4:
321 can be fit into 1863 5 times, resulting in a remainder of 258.
The number 5 becomes the next digit in our result. 
Result so far: 5.0
The remainder is 258 after subtracting 1605 from 1863.
Bring next digit (7) of the dividend behind the 258 and repeat the process: 2587 / 321

Step 5:
If we divide 2587 by 321, we get 8 and a remainder of 19.
Record the quotient 8 as the next digit in the result. 
Result so far: 58.0
If we subtract 2568 from 2587, we get 19.
Fetch the next digit (3) from the dividend, attach it to 19 and continue: 193 / 321

Advancing to step 6:
When dividing 193 by 321, we get 0 with a remainder of 193.
The next digit of our result is 0. 
Result so far: 580.0
If we subtract 0 from 193, we get 193.
Grab the next digit (2) from the dividend, add it to 193, then carry on: 1932 / 321

Advancing to step 7:
321 goes into 1932 6 times with a remainder of 6.
Put 6 as the next digit of the answer. 
Result so far: 5806.0
The remainder is 6 after subtracting 1926 from 1932.
Grab the next digit (9) from the dividend, add it to 6, then carry on: 69 / 321

Moving on to step 8:
When dividing 69 by 321, we get 0 with a remainder of 69.
The next digit of our result is 0. 
Result so far: 58060.0
Subtract 0 from 69 to get 69.
Since there are no more digits in the dividend, we add a zero to the remainder making it 690, and continue the process.

Going ahead to step 9:
If we divide 690 by 321, we get 2 and a remainder of 48.
Record the quotient 2 as the next digit in the result. 
Result so far: 58060.2
Subtracting 642 from 690 leaves us with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Going ahead to step 10:
321 goes into 480 1 times with a remainder of 159.
The number 1 becomes the next digit in our result. 
Result so far: 58060.21
Subtracting 321 from 480 leaves us with 159.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1590, and continue the process.

Step 11:
The number 321 fits into 1590 4 times, leaving a remainder of 306.
Put 4 as the next digit of the answer. 
Result so far: 58060.214
The remainder is 306 after subtracting 1284 from 1590.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3060, and continue the process.

On to step 12:
If we divide 3060 by 321, we get 9 and a remainder of 171.
Put 9 as the next digit of the answer. 
Result so far: 58060.2149
The remainder is 171 after subtracting 2889 from 3060.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1710, and continue the process.

Step 13:
When dividing 1710 by 321, we get 5 with a remainder of 105.
The number 5 becomes the next digit in our result. 
Result so far: 58060.21495
If we subtract 1605 from 1710, we get 105.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1050, and continue the process.

Advancing to step 14:
1050 divided by 321 is 3 with a remainder of 87.
The number 3 becomes the next digit in our result. 
Result so far: 58060.214953
Subtract 963 from 1050 to get 87.
Since there are no more digits in the dividend, we add a zero to the remainder making it 870, and continue the process.

Let's proceed to step 15:
870 divided by 321 is 2 with a remainder of 228.
The number 2 becomes the next digit in our result. 
Result so far: 58060.2149532
Subtract 642 from 870 to get 228.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2280, and continue the process.

Advancing to step 16:
321 can be fit into 2280 7 times, resulting in a remainder of 33.
The next digit of our result is 7. 
Result so far: 58060.21495327
If we take 2247 away from 2280, we end up with 33.
Since there are no more digits in the dividend, we add a zero to the remainder making it 330, and continue the process.

The final result is 58060.21495327 with a remainder of 3.3e-08.