We're dividing 25311584 by 644 
Our goal is to divide 25311584 by 644.

Let's proceed to step 1:
When dividing 2 by 644, we get 0 with a remainder of 2.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Include the next digit (5) from the dividend after 2, then repeat: 25 / 644

Moving on to step 2:
The number 644 fits into 25 0 times, leaving a remainder of 25.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 25, we end up with 25.
Grab the next digit (3) from the dividend, add it to 25, then carry on: 253 / 644

Let's proceed to step 3:
The number 644 fits into 253 0 times, leaving a remainder of 253.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 253, we get 253.
Append the next digit (1) from the dividend to 253 and continue with: 2531 / 644

Advancing to step 4:
644 can be fit into 2531 3 times, resulting in a remainder of 599.
Write down 3 as next digit of the result. 
Result so far: 3.0
If we subtract 1932 from 2531, we get 599.
Include the next digit (1) from the dividend after 599, then repeat: 5991 / 644

Step 5:
644 goes into 5991 9 times with a remainder of 195.
Record the quotient 9 as the next digit in the result. 
Result so far: 39.0
If we take 5796 away from 5991, we end up with 195.
Fetch the next digit (5) from the dividend, attach it to 195 and continue: 1955 / 644

On to step 6:
The number 644 fits into 1955 3 times, leaving a remainder of 23.
The number 3 becomes the next digit in our result. 
Result so far: 393.0
Subtract 1932 from 1955 to get 23.
Grab the next digit (8) from the dividend, add it to 23, then carry on: 238 / 644

Going ahead to step 7:
When dividing 238 by 644, we get 0 with a remainder of 238.
Put 0 as the next digit of the answer. 
Result so far: 3930.0
If we subtract 0 from 238, we get 238.
Take the next digit (4) from the dividend and append it to 238, then repeat: 2384 / 644

Advancing to step 8:
The number 644 fits into 2384 3 times, leaving a remainder of 452.
Write down 3 as next digit of the result. 
Result so far: 39303.0
Subtracting 1932 from 2384 leaves us with 452.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4520, and continue the process.

Step 9:
644 can be fit into 4520 7 times, resulting in a remainder of 12.
The next digit of our result is 7. 
Result so far: 39303.7
The remainder is 12 after subtracting 4508 from 4520.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 10:
644 can be fit into 120 0 times, resulting in a remainder of 120.
The next digit of our result is 0. 
Result so far: 39303.7
Deduct 0 from 120 and we're left with 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

Going ahead to step 11:
The number 644 fits into 1200 1 times, leaving a remainder of 556.
Record the quotient 1 as the next digit in the result. 
Result so far: 39303.701
The remainder is 556 after subtracting 644 from 1200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5560, and continue the process.

Advancing to step 12:
The number 644 fits into 5560 8 times, leaving a remainder of 408.
Put 8 as the next digit of the answer. 
Result so far: 39303.7018
Subtract 5152 from 5560 to get 408.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4080, and continue the process.

Step 13:
If we divide 4080 by 644, we get 6 and a remainder of 216.
The next digit of our result is 6. 
Result so far: 39303.70186
Subtracting 3864 from 4080 leaves us with 216.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2160, and continue the process.

Advancing to step 14:
644 goes into 2160 3 times with a remainder of 228.
Use 3 as the next digit of our solution. 
Result so far: 39303.701863
Subtract 1932 from 2160 to get 228.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2280, and continue the process.

Advancing to step 15:
644 goes into 2280 3 times with a remainder of 348.
The next digit of our result is 3. 
Result so far: 39303.7018633
If we subtract 1932 from 2280, we get 348.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3480, and continue the process.

The final result is 39303.7018633 with a remainder of 3.48e-06.