640040 divided by 81 
We want to figure out the number of times 640040 can be divided by 81.

On to step 1:
When dividing 6 by 81, we get 0 with a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 6, we get 6.
Append the next digit (4) from the dividend to 6 and continue with: 64 / 81

Let's proceed to step 2:
64 divided by 81 is 0 with a remainder of 64.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 64 to get 64.
Append the next digit (0) from the dividend to 64 and continue with: 640 / 81

Advancing to step 3:
When dividing 640 by 81, we get 7 with a remainder of 73.
The number 7 becomes the next digit in our result. 
Result so far: 7.0
Deduct 567 from 640 and we're left with 73.
Include the next digit (0) from the dividend after 73, then repeat: 730 / 81

On to step 4:
If we divide 730 by 81, we get 9 and a remainder of 1.
Use 9 as the next digit of our solution. 
Result so far: 79.0
If we take 729 away from 730, we end up with 1.
Bring next digit (4) of the dividend behind the 1 and repeat the process: 14 / 81

Step 5:
When dividing 14 by 81, we get 0 with a remainder of 14.
Write down 0 as next digit of the result. 
Result so far: 790.0
If we subtract 0 from 14, we get 14.
Include the next digit (0) from the dividend after 14, then repeat: 140 / 81

On to step 6:
81 goes into 140 1 times with a remainder of 59.
Record the quotient 1 as the next digit in the result. 
Result so far: 7901.0
If we subtract 81 from 140, we get 59.
Since there are no more digits in the dividend, we add a zero to the remainder making it 590, and continue the process.

Going ahead to step 7:
The number 81 fits into 590 7 times, leaving a remainder of 23.
The next digit of our result is 7. 
Result so far: 7901.7
The remainder is 23 after subtracting 567 from 590.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

Step 8:
230 divided by 81 is 2 with a remainder of 68.
Write down 2 as next digit of the result. 
Result so far: 7901.72
If we take 162 away from 230, we end up with 68.
Since there are no more digits in the dividend, we add a zero to the remainder making it 680, and continue the process.

Advancing to step 9:
If we divide 680 by 81, we get 8 and a remainder of 32.
Write down 8 as next digit of the result. 
Result so far: 7901.728
Subtract 648 from 680 to get 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Going ahead to step 10:
If we divide 320 by 81, we get 3 and a remainder of 77.
Record the quotient 3 as the next digit in the result. 
Result so far: 7901.7283
Subtract 243 from 320 to get 77.
Since there are no more digits in the dividend, we add a zero to the remainder making it 770, and continue the process.

Step 11:
If we divide 770 by 81, we get 9 and a remainder of 41.
The number 9 becomes the next digit in our result. 
Result so far: 7901.72839
If we subtract 729 from 770, we get 41.
Since there are no more digits in the dividend, we add a zero to the remainder making it 410, and continue the process.

Moving on to step 12:
When dividing 410 by 81, we get 5 with a remainder of 5.
Write down 5 as next digit of the result. 
Result so far: 7901.728395
If we subtract 405 from 410, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 13:
81 goes into 50 0 times with a remainder of 50.
Record the quotient 0 as the next digit in the result. 
Result so far: 7901.728395
If we subtract 0 from 50, we get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Moving on to step 14:
81 can be fit into 500 6 times, resulting in a remainder of 14.
The number 6 becomes the next digit in our result. 
Result so far: 7901.72839506
If we subtract 486 from 500, we get 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

The quotient of the division is 7901.72839506, and the remainder is 1.4e-08.