We look at the division of 28608651 by 644 
The aim is to understand the frequency of 644 in 28608651.

Advancing to step 1:
644 can be fit into 2 0 times, resulting in a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Include the next digit (8) from the dividend after 2, then repeat: 28 / 644

Going ahead to step 2:
644 goes into 28 0 times with a remainder of 28.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 28, we end up with 28.
Grab the next digit (6) from the dividend, add it to 28, then carry on: 286 / 644

On to step 3:
644 goes into 286 0 times with a remainder of 286.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 286, we end up with 286.
Bring next digit (0) of the dividend behind the 286 and repeat the process: 2860 / 644

On to step 4:
If we divide 2860 by 644, we get 4 and a remainder of 284.
Write down 4 as next digit of the result. 
Result so far: 4.0
If we take 2576 away from 2860, we end up with 284.
Bring next digit (8) of the dividend behind the 284 and repeat the process: 2848 / 644

Step 5:
644 goes into 2848 4 times with a remainder of 272.
Use 4 as the next digit of our solution. 
Result so far: 44.0
If we subtract 2576 from 2848, we get 272.
Bring next digit (6) of the dividend behind the 272 and repeat the process: 2726 / 644

Moving on to step 6:
When dividing 2726 by 644, we get 4 with a remainder of 150.
Record the quotient 4 as the next digit in the result. 
Result so far: 444.0
If we subtract 2576 from 2726, we get 150.
Grab the next digit (5) from the dividend, add it to 150, then carry on: 1505 / 644

Step 7:
The number 644 fits into 1505 2 times, leaving a remainder of 217.
Write down 2 as next digit of the result. 
Result so far: 4442.0
Deduct 1288 from 1505 and we're left with 217.
Append the next digit (1) from the dividend to 217 and continue with: 2171 / 644

Let's proceed to step 8:
When dividing 2171 by 644, we get 3 with a remainder of 239.
Use 3 as the next digit of our solution. 
Result so far: 44423.0
Subtracting 1932 from 2171 leaves us with 239.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2390, and continue the process.

On to step 9:
2390 divided by 644 is 3 with a remainder of 458.
Use 3 as the next digit of our solution. 
Result so far: 44423.3
Deduct 1932 from 2390 and we're left with 458.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4580, and continue the process.

Moving on to step 10:
When dividing 4580 by 644, we get 7 with a remainder of 72.
The number 7 becomes the next digit in our result. 
Result so far: 44423.37
If we take 4508 away from 4580, we end up with 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

Moving on to step 11:
The number 644 fits into 720 1 times, leaving a remainder of 76.
Write down 1 as next digit of the result. 
Result so far: 44423.371
The remainder is 76 after subtracting 644 from 720.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

Step 12:
644 can be fit into 760 1 times, resulting in a remainder of 116.
Record the quotient 1 as the next digit in the result. 
Result so far: 44423.3711
The remainder is 116 after subtracting 644 from 760.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1160, and continue the process.

In conclusion, the division gives 44423.3711 with a balance of 0.00116.