Let's divide 21105469 by 509
The aim is to understand the frequency of 509 in 21105469.

Step 1:
2 divided by 509 is 0 with a remainder of 2.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 2 leaves us with 2.
Include the next digit (1) from the dividend after 2, then repeat: 21 / 509

Moving on to step 2:
When dividing 21 by 509, we get 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.
Include the next digit (1) from the dividend after 21, then repeat: 211 / 509

Going ahead to step 3:
509 goes into 211 0 times with a remainder of 211.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 211 and we're left with 211.
Append the next digit (0) from the dividend to 211 and continue with: 2110 / 509

Going ahead to step 4:
509 goes into 2110 4 times with a remainder of 74.
The number 4 becomes the next digit in our result. 
Result so far: 4.0
Subtract 2036 from 2110 to get 74.
Include the next digit (5) from the dividend after 74, then repeat: 745 / 509

Let's proceed to step 5:
745 divided by 509 is 1 with a remainder of 236.
Record the quotient 1 as the next digit in the result. 
Result so far: 41.0
Deduct 509 from 745 and we're left with 236.
Fetch the next digit (4) from the dividend, attach it to 236 and continue: 2364 / 509

Let's proceed to step 6:
509 can be fit into 2364 4 times, resulting in a remainder of 328.
The number 4 becomes the next digit in our result. 
Result so far: 414.0
The remainder is 328 after subtracting 2036 from 2364.
Include the next digit (6) from the dividend after 328, then repeat: 3286 / 509

Moving on to step 7:
The number 509 fits into 3286 6 times, leaving a remainder of 232.
Write down 6 as next digit of the result. 
Result so far: 4146.0
If we take 3054 away from 3286, we end up with 232.
Fetch the next digit (9) from the dividend, attach it to 232 and continue: 2329 / 509

Let's proceed to step 8:
509 can be fit into 2329 4 times, resulting in a remainder of 293.
Use 4 as the next digit of our solution. 
Result so far: 41464.0
The remainder is 293 after subtracting 2036 from 2329.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2930, and continue the process.

Step 9:
509 can be fit into 2930 5 times, resulting in a remainder of 385.
The next digit of our result is 5. 
Result so far: 41464.5
If we subtract 2545 from 2930, we get 385.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3850, and continue the process.

Let's proceed to step 10:
If we divide 3850 by 509, we get 7 and a remainder of 287.
Write down 7 as next digit of the result. 
Result so far: 41464.57
If we take 3563 away from 3850, we end up with 287.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2870, and continue the process.

Moving on to step 11:
509 can be fit into 2870 5 times, resulting in a remainder of 325.
Write down 5 as next digit of the result. 
Result so far: 41464.575
If we take 2545 away from 2870, we end up with 325.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3250, and continue the process.

Let's proceed to step 12:
3250 divided by 509 is 6 with a remainder of 196.
The next digit of our result is 6. 
Result so far: 41464.5756
Subtract 3054 from 3250 to get 196.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1960, and continue the process.

Going ahead to step 13:
The number 509 fits into 1960 3 times, leaving a remainder of 433.
The next digit of our result is 3. 
Result so far: 41464.57563
If we subtract 1527 from 1960, we get 433.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4330, and continue the process.

Going ahead to step 14:
509 goes into 4330 8 times with a remainder of 258.
Record the quotient 8 as the next digit in the result. 
Result so far: 41464.575638
If we take 4072 away from 4330, we end up with 258.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2580, and continue the process.

Going ahead to step 15:
509 goes into 2580 5 times with a remainder of 35.
The number 5 becomes the next digit in our result. 
Result so far: 41464.5756385
Subtracting 2545 from 2580 leaves us with 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

On to step 16:
When dividing 350 by 509, we get 0 with a remainder of 350.
The number 0 becomes the next digit in our result. 
Result so far: 41464.5756385
Subtract 0 from 350 to get 350.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3500, and continue the process.

The quotient of the division is 41464.5756385, and the remainder is 3.5e-07.