We look at the division of 21100709 by 604 
The aim is to understand the frequency of 604 in 21100709.

Let's proceed to step 1:
When dividing 2 by 604, we get 0 with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 2 and we're left with 2.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 604

Going ahead to step 2:
21 divided by 604 is 0 with a remainder of 21.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 21 to get 21.
Take the next digit (1) from the dividend and append it to 21, then repeat: 211 / 604

Step 3:
When dividing 211 by 604, we get 0 with a remainder of 211.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 211 after subtracting 0 from 211.
Grab the next digit (0) from the dividend, add it to 211, then carry on: 2110 / 604

Going ahead to step 4:
2110 divided by 604 is 3 with a remainder of 298.
Put 3 as the next digit of the answer. 
Result so far: 3.0
If we subtract 1812 from 2110, we get 298.
Fetch the next digit (0) from the dividend, attach it to 298 and continue: 2980 / 604

Step 5:
When dividing 2980 by 604, we get 4 with a remainder of 564.
Write down 4 as next digit of the result. 
Result so far: 34.0
If we subtract 2416 from 2980, we get 564.
Take the next digit (7) from the dividend and append it to 564, then repeat: 5647 / 604

Let's proceed to step 6:
5647 divided by 604 is 9 with a remainder of 211.
Write down 9 as next digit of the result. 
Result so far: 349.0
The remainder is 211 after subtracting 5436 from 5647.
Bring next digit (0) of the dividend behind the 211 and repeat the process: 2110 / 604

Going ahead to step 7:
604 can be fit into 2110 3 times, resulting in a remainder of 298.
The next digit of our result is 3. 
Result so far: 3493.0
Deduct 1812 from 2110 and we're left with 298.
Append the next digit (9) from the dividend to 298 and continue with: 2989 / 604

Going ahead to step 8:
604 can be fit into 2989 4 times, resulting in a remainder of 573.
Put 4 as the next digit of the answer. 
Result so far: 34934.0
Subtract 2416 from 2989 to get 573.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5730, and continue the process.

Moving on to step 9:
When dividing 5730 by 604, we get 9 with a remainder of 294.
Put 9 as the next digit of the answer. 
Result so far: 34934.9
If we subtract 5436 from 5730, we get 294.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2940, and continue the process.

Step 10:
The number 604 fits into 2940 4 times, leaving a remainder of 524.
Put 4 as the next digit of the answer. 
Result so far: 34934.94
Subtract 2416 from 2940 to get 524.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5240, and continue the process.

Advancing to step 11:
604 can be fit into 5240 8 times, resulting in a remainder of 408.
The next digit of our result is 8. 
Result so far: 34934.948
Subtracting 4832 from 5240 leaves us with 408.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4080, and continue the process.

Let's proceed to step 12:
The number 604 fits into 4080 6 times, leaving a remainder of 456.
Record the quotient 6 as the next digit in the result. 
Result so far: 34934.9486
The remainder is 456 after subtracting 3624 from 4080.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4560, and continue the process.

On to step 13:
If we divide 4560 by 604, we get 7 and a remainder of 332.
Use 7 as the next digit of our solution. 
Result so far: 34934.94867
If we take 4228 away from 4560, we end up with 332.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3320, and continue the process.

Going ahead to step 14:
604 can be fit into 3320 5 times, resulting in a remainder of 300.
Record the quotient 5 as the next digit in the result. 
Result so far: 34934.948675
Subtract 3020 from 3320 to get 300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3000, and continue the process.

Going ahead to step 15:
3000 divided by 604 is 4 with a remainder of 584.
Write down 4 as next digit of the result. 
Result so far: 34934.9486754
Subtract 2416 from 3000 to get 584.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5840, and continue the process.

Step 16:
If we divide 5840 by 604, we get 9 and a remainder of 404.
Write down 9 as next digit of the result. 
Result so far: 34934.94867549
If we take 5436 away from 5840, we end up with 404.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4040, and continue the process.

After the division, we end up with 34934.94867549 and a remainder of 4.04e-07.