860591 ÷ 15 
Let's see how many times 15 fits into 860591.

Moving on to step 1:
8 divided by 15 is 0 with a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Append the next digit (6) from the dividend to 8 and continue with: 86 / 15

Going ahead to step 2:
15 goes into 86 5 times with a remainder of 11.
The next digit of our result is 5. 
Result so far: 5.0
If we subtract 75 from 86, we get 11.
Include the next digit (0) from the dividend after 11, then repeat: 110 / 15

Advancing to step 3:
15 goes into 110 7 times with a remainder of 5.
Write down 7 as next digit of the result. 
Result so far: 57.0
The remainder is 5 after subtracting 105 from 110.
Include the next digit (5) from the dividend after 5, then repeat: 55 / 15

Step 4:
If we divide 55 by 15, we get 3 and a remainder of 10.
The number 3 becomes the next digit in our result. 
Result so far: 573.0
If we take 45 away from 55, we end up with 10.
Fetch the next digit (9) from the dividend, attach it to 10 and continue: 109 / 15

Advancing to step 5:
If we divide 109 by 15, we get 7 and a remainder of 4.
Write down 7 as next digit of the result. 
Result so far: 5737.0
Subtracting 105 from 109 leaves us with 4.
Take the next digit (1) from the dividend and append it to 4, then repeat: 41 / 15

On to step 6:
The number 15 fits into 41 2 times, leaving a remainder of 11.
Use 2 as the next digit of our solution. 
Result so far: 57372.0
Subtract 30 from 41 to get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Let's proceed to step 7:
The number 15 fits into 110 7 times, leaving a remainder of 5.
The number 7 becomes the next digit in our result. 
Result so far: 57372.7
If we subtract 105 from 110, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 8:
The number 15 fits into 50 3 times, leaving a remainder of 5.
The next digit of our result is 3. 
Result so far: 57372.73
Subtracting 45 from 50 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 9:
The number 15 fits into 50 3 times, leaving a remainder of 5.
The number 3 becomes the next digit in our result. 
Result so far: 57372.733
Subtracting 45 from 50 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

The quotient of the division is 57372.733, and the remainder is 0.0005.