We divide 510648 by 20
We want to figure out the number of times 510648 can be divided by 20.

Going ahead to step 1:
5 divided by 20 is 0 with a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 5, we get 5.
Bring next digit (1) of the dividend behind the 5 and repeat the process: 51 / 20

Moving on to step 2:
If we divide 51 by 20, we get 2 and a remainder of 11.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
Deduct 40 from 51 and we're left with 11.
Include the next digit (0) from the dividend after 11, then repeat: 110 / 20

Going ahead to step 3:
20 goes into 110 5 times with a remainder of 10.
The number 5 becomes the next digit in our result. 
Result so far: 25.0
Subtracting 100 from 110 leaves us with 10.
Fetch the next digit (6) from the dividend, attach it to 10 and continue: 106 / 20

Moving on to step 4:
20 can be fit into 106 5 times, resulting in a remainder of 6.
Record the quotient 5 as the next digit in the result. 
Result so far: 255.0
If we take 100 away from 106, we end up with 6.
Include the next digit (4) from the dividend after 6, then repeat: 64 / 20

Let's proceed to step 5:
If we divide 64 by 20, we get 3 and a remainder of 4.
Put 3 as the next digit of the answer. 
Result so far: 2553.0
Deduct 60 from 64 and we're left with 4.
Bring next digit (8) of the dividend behind the 4 and repeat the process: 48 / 20

Let's proceed to step 6:
48 divided by 20 is 2 with a remainder of 8.
The next digit of our result is 2. 
Result so far: 25532.0
Deduct 40 from 48 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 7:
80 divided by 20 is 4 with a remainder of 0.
Record the quotient 4 as the next digit in the result. 
Result so far: 25532.4
The remainder is 0 after subtracting 80 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 8:
When dividing 0 by 20, we get 0 with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 25532.4
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 9:
20 can be fit into 0 0 times, resulting in a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 25532.4
Subtracting 0 from 0 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.

The quotient of the division is 25532.4, and the remainder is 0.0.