We look at the division of 516405 by 31 
We want to divide 516405 by 31.

Step 1:
The number 31 fits into 5 0 times, leaving a remainder of 5.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 5 to get 5.
Take the next digit (1) from the dividend and append it to 5, then repeat: 51 / 31

Step 2:
The number 31 fits into 51 1 times, leaving a remainder of 20.
The next digit of our result is 1. 
Result so far: 1.0
If we take 31 away from 51, we end up with 20.
Grab the next digit (6) from the dividend, add it to 20, then carry on: 206 / 31

Let's proceed to step 3:
If we divide 206 by 31, we get 6 and a remainder of 20.
Write down 6 as next digit of the result. 
Result so far: 16.0
Subtract 186 from 206 to get 20.
Grab the next digit (4) from the dividend, add it to 20, then carry on: 204 / 31

Moving on to step 4:
If we divide 204 by 31, we get 6 and a remainder of 18.
The number 6 becomes the next digit in our result. 
Result so far: 166.0
Subtract 186 from 204 to get 18.
Grab the next digit (0) from the dividend, add it to 18, then carry on: 180 / 31

Going ahead to step 5:
The number 31 fits into 180 5 times, leaving a remainder of 25.
Put 5 as the next digit of the answer. 
Result so far: 1665.0
If we take 155 away from 180, we end up with 25.
Fetch the next digit (5) from the dividend, attach it to 25 and continue: 255 / 31

On to step 6:
The number 31 fits into 255 8 times, leaving a remainder of 7.
Write down 8 as next digit of the result. 
Result so far: 16658.0
Deduct 248 from 255 and we're left with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Going ahead to step 7:
70 divided by 31 is 2 with a remainder of 8.
Write down 2 as next digit of the result. 
Result so far: 16658.2
If we subtract 62 from 70, we get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 8:
31 can be fit into 80 2 times, resulting in a remainder of 18.
The next digit of our result is 2. 
Result so far: 16658.22
Subtract 62 from 80 to get 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

The final outcome is 16658.22, with a leftover of 0.018.