640104 divided by 20 
We want to figure out the number of times 640104 can be divided by 20.

Going ahead to step 1:
6 divided by 20 is 0 with a remainder of 6.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Append the next digit (4) from the dividend to 6 and continue with: 64 / 20

Advancing to step 2:
20 can be fit into 64 3 times, resulting in a remainder of 4.
Put 3 as the next digit of the answer. 
Result so far: 3.0
If we subtract 60 from 64, we get 4.
Include the next digit (0) from the dividend after 4, then repeat: 40 / 20

Moving on to step 3:
40 divided by 20 is 2 with a remainder of 0.
Write down 2 as next digit of the result. 
Result so far: 32.0
If we subtract 40 from 40, we get 0.
Bring next digit (1) of the dividend behind the 0 and repeat the process: 1 / 20

Advancing to step 4:
If we divide 1 by 20, we get 0 and a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 320.0
Subtract 0 from 1 to get 1.
Fetch the next digit (0) from the dividend, attach it to 1 and continue: 10 / 20

Let's proceed to step 5:
10 divided by 20 is 0 with a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 3200.0
The remainder is 10 after subtracting 0 from 10.
Take the next digit (4) from the dividend and append it to 10, then repeat: 104 / 20

Going ahead to step 6:
20 goes into 104 5 times with a remainder of 4.
Use 5 as the next digit of our solution. 
Result so far: 32005.0
Subtract 100 from 104 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 7:
When dividing 40 by 20, we get 2 with a remainder of 0.
The next digit of our result is 2. 
Result so far: 32005.2
Subtracting 40 from 40 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 8:
The number 20 fits into 0 0 times, leaving a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 32005.2
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 9:
20 goes into 0 0 times with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 32005.2
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 32005.2, with a leftover of 0.0.