We look at the division of 8172639 by 591 
The aim is to understand the frequency of 591 in 8172639.

Moving on to step 1:
The number 591 fits into 8 0 times, leaving a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Include the next digit (1) from the dividend after 8, then repeat: 81 / 591

Advancing to step 2:
If we divide 81 by 591, we get 0 and a remainder of 81.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 81, we end up with 81.
Take the next digit (7) from the dividend and append it to 81, then repeat: 817 / 591

Step 3:
The number 591 fits into 817 1 times, leaving a remainder of 226.
The next digit of our result is 1. 
Result so far: 1.0
If we take 591 away from 817, we end up with 226.
Append the next digit (2) from the dividend to 226 and continue with: 2262 / 591

Advancing to step 4:
2262 divided by 591 is 3 with a remainder of 489.
Record the quotient 3 as the next digit in the result. 
Result so far: 13.0
If we subtract 1773 from 2262, we get 489.
Take the next digit (6) from the dividend and append it to 489, then repeat: 4896 / 591

Step 5:
If we divide 4896 by 591, we get 8 and a remainder of 168.
The number 8 becomes the next digit in our result. 
Result so far: 138.0
Deduct 4728 from 4896 and we're left with 168.
Fetch the next digit (3) from the dividend, attach it to 168 and continue: 1683 / 591

Moving on to step 6:
1683 divided by 591 is 2 with a remainder of 501.
Write down 2 as next digit of the result. 
Result so far: 1382.0
If we take 1182 away from 1683, we end up with 501.
Take the next digit (9) from the dividend and append it to 501, then repeat: 5019 / 591

On to step 7:
591 can be fit into 5019 8 times, resulting in a remainder of 291.
Record the quotient 8 as the next digit in the result. 
Result so far: 13828.0
Subtract 4728 from 5019 to get 291.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2910, and continue the process.

Step 8:
When dividing 2910 by 591, we get 4 with a remainder of 546.
Put 4 as the next digit of the answer. 
Result so far: 13828.4
If we subtract 2364 from 2910, we get 546.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5460, and continue the process.

Moving on to step 9:
591 goes into 5460 9 times with a remainder of 141.
Use 9 as the next digit of our solution. 
Result so far: 13828.49
Subtracting 5319 from 5460 leaves us with 141.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1410, and continue the process.

Going ahead to step 10:
If we divide 1410 by 591, we get 2 and a remainder of 228.
Write down 2 as next digit of the result. 
Result so far: 13828.492
The remainder is 228 after subtracting 1182 from 1410.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2280, and continue the process.

On to step 11:
If we divide 2280 by 591, we get 3 and a remainder of 507.
The next digit of our result is 3. 
Result so far: 13828.4923
Subtracting 1773 from 2280 leaves us with 507.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5070, and continue the process.

Let's proceed to step 12:
591 goes into 5070 8 times with a remainder of 342.
Put 8 as the next digit of the answer. 
Result so far: 13828.49238
The remainder is 342 after subtracting 4728 from 5070.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3420, and continue the process.

Moving on to step 13:
3420 divided by 591 is 5 with a remainder of 465.
Put 5 as the next digit of the answer. 
Result so far: 13828.492385
Subtract 2955 from 3420 to get 465.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4650, and continue the process.

Step 14:
When dividing 4650 by 591, we get 7 with a remainder of 513.
The number 7 becomes the next digit in our result. 
Result so far: 13828.4923857
Deduct 4137 from 4650 and we're left with 513.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5130, and continue the process.

Let's proceed to step 15:
If we divide 5130 by 591, we get 8 and a remainder of 402.
Put 8 as the next digit of the answer. 
Result so far: 13828.49238578
If we subtract 4728 from 5130, we get 402.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4020, and continue the process.

The final outcome is 13828.49238578, with a leftover of 4.02e-07.