539991 ÷ 25 
We're looking to find how many times 25 goes into 539991.

Advancing to step 1:
The number 25 fits into 5 0 times, leaving a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 5 leaves us with 5.
Take the next digit (3) from the dividend and append it to 5, then repeat: 53 / 25

On to step 2:
The number 25 fits into 53 2 times, leaving a remainder of 3.
The next digit of our result is 2. 
Result so far: 2.0
Subtract 50 from 53 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 25

Moving on to step 3:
25 can be fit into 39 1 times, resulting in a remainder of 14.
The next digit of our result is 1. 
Result so far: 21.0
If we subtract 25 from 39, we get 14.
Append the next digit (9) from the dividend to 14 and continue with: 149 / 25

Moving on to step 4:
The number 25 fits into 149 5 times, leaving a remainder of 24.
Record the quotient 5 as the next digit in the result. 
Result so far: 215.0
If we take 125 away from 149, we end up with 24.
Bring next digit (9) of the dividend behind the 24 and repeat the process: 249 / 25

Step 5:
If we divide 249 by 25, we get 9 and a remainder of 24.
Record the quotient 9 as the next digit in the result. 
Result so far: 2159.0
Subtracting 225 from 249 leaves us with 24.
Bring next digit (1) of the dividend behind the 24 and repeat the process: 241 / 25

Going ahead to step 6:
25 can be fit into 241 9 times, resulting in a remainder of 16.
The number 9 becomes the next digit in our result. 
Result so far: 21599.0
The remainder is 16 after subtracting 225 from 241.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Let's proceed to step 7:
25 can be fit into 160 6 times, resulting in a remainder of 10.
Use 6 as the next digit of our solution. 
Result so far: 21599.6
If we subtract 150 from 160, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Moving on to step 8:
If we divide 100 by 25, we get 4 and a remainder of 0.
Write down 4 as next digit of the result. 
Result so far: 21599.64
If we subtract 100 from 100, 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.

Going ahead to step 9:
25 goes into 0 0 times with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 21599.64
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.

Going ahead to step 10:
If we divide 0 by 25, we get 0 and a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 21599.64
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 21599.64, with a leftover of 0.0.