We look at the division of 86586411 by 870 
Our goal is to divide 86586411 by 870.

Step 1:
The number 870 fits into 8 0 times, leaving a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 8, we end up with 8.
Include the next digit (6) from the dividend after 8, then repeat: 86 / 870

Let's proceed to step 2:
If we divide 86 by 870, we get 0 and a remainder of 86.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 86, we get 86.
Take the next digit (5) from the dividend and append it to 86, then repeat: 865 / 870

Step 3:
870 can be fit into 865 0 times, resulting in a remainder of 865.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 865 after subtracting 0 from 865.
Fetch the next digit (8) from the dividend, attach it to 865 and continue: 8658 / 870

Step 4:
8658 divided by 870 is 9 with a remainder of 828.
The next digit of our result is 9. 
Result so far: 9.0
The remainder is 828 after subtracting 7830 from 8658.
Bring next digit (6) of the dividend behind the 828 and repeat the process: 8286 / 870

Step 5:
The number 870 fits into 8286 9 times, leaving a remainder of 456.
Use 9 as the next digit of our solution. 
Result so far: 99.0
If we take 7830 away from 8286, we end up with 456.
Grab the next digit (4) from the dividend, add it to 456, then carry on: 4564 / 870

Let's proceed to step 6:
4564 divided by 870 is 5 with a remainder of 214.
Put 5 as the next digit of the answer. 
Result so far: 995.0
The remainder is 214 after subtracting 4350 from 4564.
Bring next digit (1) of the dividend behind the 214 and repeat the process: 2141 / 870

On to step 7:
2141 divided by 870 is 2 with a remainder of 401.
The next digit of our result is 2. 
Result so far: 9952.0
The remainder is 401 after subtracting 1740 from 2141.
Append the next digit (1) from the dividend to 401 and continue with: 4011 / 870

Let's proceed to step 8:
When dividing 4011 by 870, we get 4 with a remainder of 531.
The number 4 becomes the next digit in our result. 
Result so far: 99524.0
If we subtract 3480 from 4011, we get 531.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5310, and continue the process.

Step 9:
If we divide 5310 by 870, we get 6 and a remainder of 90.
The number 6 becomes the next digit in our result. 
Result so far: 99524.6
Subtracting 5220 from 5310 leaves us with 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 900, and continue the process.

Step 10:
When dividing 900 by 870, we get 1 with a remainder of 30.
Put 1 as the next digit of the answer. 
Result so far: 99524.61
Subtract 870 from 900 to get 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Step 11:
If we divide 300 by 870, we get 0 and a remainder of 300.
The number 0 becomes the next digit in our result. 
Result so far: 99524.61
Deduct 0 from 300 and we're left with 300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3000, and continue the process.

Moving on to step 12:
870 can be fit into 3000 3 times, resulting in a remainder of 390.
Record the quotient 3 as the next digit in the result. 
Result so far: 99524.6103
If we subtract 2610 from 3000, we get 390.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3900, and continue the process.

Step 13:
870 can be fit into 3900 4 times, resulting in a remainder of 420.
Record the quotient 4 as the next digit in the result. 
Result so far: 99524.61034
Subtracting 3480 from 3900 leaves us with 420.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4200, and continue the process.

Moving on to step 14:
When dividing 4200 by 870, we get 4 with a remainder of 720.
Record the quotient 4 as the next digit in the result. 
Result so far: 99524.610344
The remainder is 720 after subtracting 3480 from 4200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7200, and continue the process.

The final outcome is 99524.610344, with a leftover of 7.2e-05.