We look at the division of 510420 by 1 
Let's see how many times 1 fits into 510420.

Going ahead to step 1:
1 goes into 5 5 times with a remainder of 0.
The number 5 becomes the next digit in our result. 
Result so far: 5.0
If we take 5 away from 5, we end up with 0.
Append the next digit (1) from the dividend to 0 and continue with: 1 / 1

Let's proceed to step 2:
If we divide 1 by 1, we get 1 and a remainder of 0.
Record the quotient 1 as the next digit in the result. 
Result so far: 51.0
Deduct 1 from 1 and we're left with 0.
Grab the next digit (0) from the dividend, add it to 0, then carry on: 0 / 1

On to step 3:
When dividing 0 by 1, we get 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 510.0
If we subtract 0 from 0, we get 0.
Append the next digit (4) from the dividend to 0 and continue with: 4 / 1

Moving on to step 4:
If we divide 4 by 1, we get 4 and a remainder of 0.
The next digit of our result is 4. 
Result so far: 5104.0
Deduct 4 from 4 and we're left with 0.
Fetch the next digit (2) from the dividend, attach it to 0 and continue: 2 / 1

Going ahead to step 5:
When dividing 2 by 1, we get 2 with a remainder of 0.
Write down 2 as next digit of the result. 
Result so far: 51042.0
If we take 2 away from 2, we end up with 0.
Include the next digit (0) from the dividend after 0, then repeat: 0 / 1

Advancing to step 6:
The number 1 fits into 0 0 times, leaving a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 510420.0
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 7:
0 divided by 1 is 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 510420.0
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.

Step 8:
If we divide 0 by 1, we get 0 and a remainder of 0.
The next digit of our result is 0. 
Result so far: 510420.0
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 result is 510420.0 with a remainder of 0.0.