Let's divide 57215584 by 644
The aim is to understand the frequency of 644 in 57215584.

Let's proceed to step 1:
5 divided by 644 is 0 with a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 5 leaves us with 5.
Bring next digit (7) of the dividend behind the 5 and repeat the process: 57 / 644

Going ahead to step 2:
When dividing 57 by 644, we get 0 with a remainder of 57.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 57, we get 57.
Take the next digit (2) from the dividend and append it to 57, then repeat: 572 / 644

Step 3:
If we divide 572 by 644, we get 0 and a remainder of 572.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 572 to get 572.
Append the next digit (1) from the dividend to 572 and continue with: 5721 / 644

Moving on to step 4:
The number 644 fits into 5721 8 times, leaving a remainder of 569.
The next digit of our result is 8. 
Result so far: 8.0
The remainder is 569 after subtracting 5152 from 5721.
Bring next digit (5) of the dividend behind the 569 and repeat the process: 5695 / 644

Step 5:
When dividing 5695 by 644, we get 8 with a remainder of 543.
Use 8 as the next digit of our solution. 
Result so far: 88.0
Deduct 5152 from 5695 and we're left with 543.
Include the next digit (5) from the dividend after 543, then repeat: 5435 / 644

Advancing to step 6:
If we divide 5435 by 644, we get 8 and a remainder of 283.
The next digit of our result is 8. 
Result so far: 888.0
Subtracting 5152 from 5435 leaves us with 283.
Append the next digit (8) from the dividend to 283 and continue with: 2838 / 644

On to step 7:
If we divide 2838 by 644, we get 4 and a remainder of 262.
Record the quotient 4 as the next digit in the result. 
Result so far: 8884.0
Subtracting 2576 from 2838 leaves us with 262.
Bring next digit (4) of the dividend behind the 262 and repeat the process: 2624 / 644

Let's proceed to step 8:
If we divide 2624 by 644, we get 4 and a remainder of 48.
The number 4 becomes the next digit in our result. 
Result so far: 88844.0
Subtract 2576 from 2624 to get 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Let's proceed to step 9:
The number 644 fits into 480 0 times, leaving a remainder of 480.
Use 0 as the next digit of our solution. 
Result so far: 88844.0
Subtract 0 from 480 to get 480.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4800, and continue the process.

Moving on to step 10:
4800 divided by 644 is 7 with a remainder of 292.
Use 7 as the next digit of our solution. 
Result so far: 88844.07
If we subtract 4508 from 4800, we get 292.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2920, and continue the process.

Going ahead to step 11:
644 can be fit into 2920 4 times, resulting in a remainder of 344.
The next digit of our result is 4. 
Result so far: 88844.074
Subtracting 2576 from 2920 leaves us with 344.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3440, and continue the process.

Advancing to step 12:
644 goes into 3440 5 times with a remainder of 220.
Put 5 as the next digit of the answer. 
Result so far: 88844.0745
If we subtract 3220 from 3440, we get 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2200, and continue the process.

Advancing to step 13:
If we divide 2200 by 644, we get 3 and a remainder of 268.
The number 3 becomes the next digit in our result. 
Result so far: 88844.07453
If we subtract 1932 from 2200, we get 268.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2680, and continue the process.

Going ahead to step 14:
The number 644 fits into 2680 4 times, leaving a remainder of 104.
Write down 4 as next digit of the result. 
Result so far: 88844.074534
Deduct 2576 from 2680 and we're left with 104.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1040, and continue the process.

Advancing to step 15:
644 can be fit into 1040 1 times, resulting in a remainder of 396.
Use 1 as the next digit of our solution. 
Result so far: 88844.0745341
Subtracting 644 from 1040 leaves us with 396.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3960, and continue the process.

On to step 16:
644 goes into 3960 6 times with a remainder of 96.
Use 6 as the next digit of our solution. 
Result so far: 88844.07453416
If we subtract 3864 from 3960, we get 96.
Since there are no more digits in the dividend, we add a zero to the remainder making it 960, and continue the process.

The final outcome is 88844.07453416, with a leftover of 9.6e-08.