We look at the division of 81128959 by 644 
We want to divide 81128959 by 644.

Step 1:
644 can be fit into 8 0 times, resulting in a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 8, we end up with 8.
Include the next digit (1) from the dividend after 8, then repeat: 81 / 644

Advancing to step 2:
644 can be fit into 81 0 times, resulting in a remainder of 81.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 81, we end up with 81.
Fetch the next digit (1) from the dividend, attach it to 81 and continue: 811 / 644

On to step 3:
When dividing 811 by 644, we get 1 with a remainder of 167.
The next digit of our result is 1. 
Result so far: 1.0
If we subtract 644 from 811, we get 167.
Grab the next digit (2) from the dividend, add it to 167, then carry on: 1672 / 644

On to step 4:
644 goes into 1672 2 times with a remainder of 384.
Put 2 as the next digit of the answer. 
Result so far: 12.0
If we subtract 1288 from 1672, we get 384.
Append the next digit (8) from the dividend to 384 and continue with: 3848 / 644

Moving on to step 5:
If we divide 3848 by 644, we get 5 and a remainder of 628.
Write down 5 as next digit of the result. 
Result so far: 125.0
Subtract 3220 from 3848 to get 628.
Include the next digit (9) from the dividend after 628, then repeat: 6289 / 644

On to step 6:
644 can be fit into 6289 9 times, resulting in a remainder of 493.
Put 9 as the next digit of the answer. 
Result so far: 1259.0
Subtracting 5796 from 6289 leaves us with 493.
Grab the next digit (5) from the dividend, add it to 493, then carry on: 4935 / 644

On to step 7:
4935 divided by 644 is 7 with a remainder of 427.
The next digit of our result is 7. 
Result so far: 12597.0
The remainder is 427 after subtracting 4508 from 4935.
Fetch the next digit (9) from the dividend, attach it to 427 and continue: 4279 / 644

Step 8:
644 goes into 4279 6 times with a remainder of 415.
Record the quotient 6 as the next digit in the result. 
Result so far: 125976.0
Subtract 3864 from 4279 to get 415.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4150, and continue the process.

Advancing to step 9:
644 can be fit into 4150 6 times, resulting in a remainder of 286.
The next digit of our result is 6. 
Result so far: 125976.6
Deduct 3864 from 4150 and we're left with 286.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2860, and continue the process.

On to step 10:
If we divide 2860 by 644, we get 4 and a remainder of 284.
Put 4 as the next digit of the answer. 
Result so far: 125976.64
The remainder is 284 after subtracting 2576 from 2860.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2840, and continue the process.

Going ahead to step 11:
When dividing 2840 by 644, we get 4 with a remainder of 264.
Write down 4 as next digit of the result. 
Result so far: 125976.644
If we take 2576 away from 2840, we end up with 264.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2640, and continue the process.

After the division, we end up with 125976.644 and a remainder of 0.0264.