21104158 ÷ 520 
The aim is to understand the frequency of 520 in 21104158.

Advancing to step 1:
520 can be fit into 2 0 times, resulting in a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Bring next digit (1) of the dividend behind the 2 and repeat the process: 21 / 520

On to step 2:
The number 520 fits into 21 0 times, leaving a remainder of 21.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 21, we end up with 21.
Include the next digit (1) from the dividend after 21, then repeat: 211 / 520

Advancing to step 3:
211 divided by 520 is 0 with a remainder of 211.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 211, we end up with 211.
Fetch the next digit (0) from the dividend, attach it to 211 and continue: 2110 / 520

Advancing to step 4:
If we divide 2110 by 520, we get 4 and a remainder of 30.
Use 4 as the next digit of our solution. 
Result so far: 4.0
The remainder is 30 after subtracting 2080 from 2110.
Include the next digit (4) from the dividend after 30, then repeat: 304 / 520

Moving on to step 5:
If we divide 304 by 520, we get 0 and a remainder of 304.
Write down 0 as next digit of the result. 
Result so far: 40.0
If we subtract 0 from 304, we get 304.
Take the next digit (1) from the dividend and append it to 304, then repeat: 3041 / 520

Advancing to step 6:
520 can be fit into 3041 5 times, resulting in a remainder of 441.
The next digit of our result is 5. 
Result so far: 405.0
Subtract 2600 from 3041 to get 441.
Append the next digit (5) from the dividend to 441 and continue with: 4415 / 520

Step 7:
520 can be fit into 4415 8 times, resulting in a remainder of 255.
Record the quotient 8 as the next digit in the result. 
Result so far: 4058.0
Subtracting 4160 from 4415 leaves us with 255.
Include the next digit (8) from the dividend after 255, then repeat: 2558 / 520

On to step 8:
The number 520 fits into 2558 4 times, leaving a remainder of 478.
Write down 4 as next digit of the result. 
Result so far: 40584.0
Deduct 2080 from 2558 and we're left with 478.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4780, and continue the process.

Going ahead to step 9:
520 can be fit into 4780 9 times, resulting in a remainder of 100.
Use 9 as the next digit of our solution. 
Result so far: 40584.9
Subtract 4680 from 4780 to get 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1000, and continue the process.

Moving on to step 10:
If we divide 1000 by 520, we get 1 and a remainder of 480.
Record the quotient 1 as the next digit in the result. 
Result so far: 40584.91
Deduct 520 from 1000 and we're left with 480.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4800, and continue the process.

Going ahead to step 11:
If we divide 4800 by 520, we get 9 and a remainder of 120.
Use 9 as the next digit of our solution. 
Result so far: 40584.919
If we subtract 4680 from 4800, we get 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

Advancing to step 12:
1200 divided by 520 is 2 with a remainder of 160.
The next digit of our result is 2. 
Result so far: 40584.9192
If we subtract 1040 from 1200, we get 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1600, and continue the process.

Step 13:
When dividing 1600 by 520, we get 3 with a remainder of 40.
The number 3 becomes the next digit in our result. 
Result so far: 40584.91923
Deduct 1560 from 1600 and we're left with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

On to step 14:
When dividing 400 by 520, we get 0 with a remainder of 400.
Put 0 as the next digit of the answer. 
Result so far: 40584.91923
Deduct 0 from 400 and we're left with 400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4000, and continue the process.

Moving on to step 15:
4000 divided by 520 is 7 with a remainder of 360.
Write down 7 as next digit of the result. 
Result so far: 40584.9192307
The remainder is 360 after subtracting 3640 from 4000.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3600, and continue the process.

Going ahead to step 16:
520 can be fit into 3600 6 times, resulting in a remainder of 480.
The number 6 becomes the next digit in our result. 
Result so far: 40584.91923076
Subtracting 3120 from 3600 leaves us with 480.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4800, and continue the process.

Our division results in 40584.91923076 with a remaining 4.8e-07.