81515233 ÷ 597 
The aim is to understand the frequency of 597 in 81515233.

Step 1:
If we divide 8 by 597, we get 0 and a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Bring next digit (1) of the dividend behind the 8 and repeat the process: 81 / 597

Moving on to step 2:
When dividing 81 by 597, we get 0 with a remainder of 81.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 81 leaves us with 81.
Bring next digit (5) of the dividend behind the 81 and repeat the process: 815 / 597

Moving on to step 3:
The number 597 fits into 815 1 times, leaving a remainder of 218.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Deduct 597 from 815 and we're left with 218.
Fetch the next digit (1) from the dividend, attach it to 218 and continue: 2181 / 597

On to step 4:
If we divide 2181 by 597, we get 3 and a remainder of 390.
The next digit of our result is 3. 
Result so far: 13.0
If we subtract 1791 from 2181, we get 390.
Append the next digit (5) from the dividend to 390 and continue with: 3905 / 597

On to step 5:
When dividing 3905 by 597, we get 6 with a remainder of 323.
Record the quotient 6 as the next digit in the result. 
Result so far: 136.0
The remainder is 323 after subtracting 3582 from 3905.
Include the next digit (2) from the dividend after 323, then repeat: 3232 / 597

Let's proceed to step 6:
597 can be fit into 3232 5 times, resulting in a remainder of 247.
Put 5 as the next digit of the answer. 
Result so far: 1365.0
Subtracting 2985 from 3232 leaves us with 247.
Bring next digit (3) of the dividend behind the 247 and repeat the process: 2473 / 597

Let's proceed to step 7:
597 can be fit into 2473 4 times, resulting in a remainder of 85.
Use 4 as the next digit of our solution. 
Result so far: 13654.0
If we take 2388 away from 2473, we end up with 85.
Include the next digit (3) from the dividend after 85, then repeat: 853 / 597

Advancing to step 8:
597 goes into 853 1 times with a remainder of 256.
Write down 1 as next digit of the result. 
Result so far: 136541.0
If we subtract 597 from 853, we get 256.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2560, and continue the process.

Advancing to step 9:
597 can be fit into 2560 4 times, resulting in a remainder of 172.
Put 4 as the next digit of the answer. 
Result so far: 136541.4
If we take 2388 away from 2560, we end up with 172.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1720, and continue the process.

Advancing to step 10:
1720 divided by 597 is 2 with a remainder of 526.
Put 2 as the next digit of the answer. 
Result so far: 136541.42
Deduct 1194 from 1720 and we're left with 526.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5260, and continue the process.

Advancing to step 11:
5260 divided by 597 is 8 with a remainder of 484.
Record the quotient 8 as the next digit in the result. 
Result so far: 136541.428
Subtracting 4776 from 5260 leaves us with 484.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4840, and continue the process.

Moving on to step 12:
4840 divided by 597 is 8 with a remainder of 64.
Use 8 as the next digit of our solution. 
Result so far: 136541.4288
Subtract 4776 from 4840 to get 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

The final result is 136541.4288 with a remainder of 0.00064.