17563452 ÷ 644 
We want to figure out the number of times 17563452 can be divided by 644.

On to step 1:
644 goes into 1 0 times with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Fetch the next digit (7) from the dividend, attach it to 1 and continue: 17 / 644

Let's proceed to step 2:
17 divided by 644 is 0 with a remainder of 17.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 17 to get 17.
Grab the next digit (5) from the dividend, add it to 17, then carry on: 175 / 644

Let's proceed to step 3:
If we divide 175 by 644, we get 0 and a remainder of 175.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 175 and we're left with 175.
Take the next digit (6) from the dividend and append it to 175, then repeat: 1756 / 644

Step 4:
When dividing 1756 by 644, we get 2 with a remainder of 468.
Use 2 as the next digit of our solution. 
Result so far: 2.0
Subtracting 1288 from 1756 leaves us with 468.
Grab the next digit (3) from the dividend, add it to 468, then carry on: 4683 / 644

On to step 5:
When dividing 4683 by 644, we get 7 with a remainder of 175.
The next digit of our result is 7. 
Result so far: 27.0
The remainder is 175 after subtracting 4508 from 4683.
Include the next digit (4) from the dividend after 175, then repeat: 1754 / 644

Advancing to step 6:
The number 644 fits into 1754 2 times, leaving a remainder of 466.
Put 2 as the next digit of the answer. 
Result so far: 272.0
Deduct 1288 from 1754 and we're left with 466.
Include the next digit (5) from the dividend after 466, then repeat: 4665 / 644

Going ahead to step 7:
If we divide 4665 by 644, we get 7 and a remainder of 157.
Write down 7 as next digit of the result. 
Result so far: 2727.0
If we take 4508 away from 4665, we end up with 157.
Include the next digit (2) from the dividend after 157, then repeat: 1572 / 644

Moving on to step 8:
644 goes into 1572 2 times with a remainder of 284.
The next digit of our result is 2. 
Result so far: 27272.0
If we subtract 1288 from 1572, we get 284.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2840, and continue the process.

Moving on to step 9:
2840 divided by 644 is 4 with a remainder of 264.
Put 4 as the next digit of the answer. 
Result so far: 27272.4
If we subtract 2576 from 2840, we get 264.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2640, and continue the process.

Going ahead to step 10:
644 goes into 2640 4 times with a remainder of 64.
Write down 4 as next digit of the result. 
Result so far: 27272.44
Subtracting 2576 from 2640 leaves us with 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Our division results in 27272.44 with a remaining 0.064.