86601250 ÷ 661 
We want to divide 86601250 by 661.

Step 1:
661 goes into 8 0 times with a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Take the next digit (6) from the dividend and append it to 8, then repeat: 86 / 661

Going ahead to step 2:
86 divided by 661 is 0 with a remainder of 86.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 86 and we're left with 86.
Bring next digit (6) of the dividend behind the 86 and repeat the process: 866 / 661

On to step 3:
When dividing 866 by 661, we get 1 with a remainder of 205.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we take 661 away from 866, we end up with 205.
Append the next digit (0) from the dividend to 205 and continue with: 2050 / 661

Step 4:
If we divide 2050 by 661, we get 3 and a remainder of 67.
Put 3 as the next digit of the answer. 
Result so far: 13.0
If we subtract 1983 from 2050, we get 67.
Grab the next digit (1) from the dividend, add it to 67, then carry on: 671 / 661

Let's proceed to step 5:
If we divide 671 by 661, we get 1 and a remainder of 10.
Put 1 as the next digit of the answer. 
Result so far: 131.0
If we take 661 away from 671, we end up with 10.
Append the next digit (2) from the dividend to 10 and continue with: 102 / 661

Going ahead to step 6:
When dividing 102 by 661, we get 0 with a remainder of 102.
Write down 0 as next digit of the result. 
Result so far: 1310.0
If we subtract 0 from 102, we get 102.
Grab the next digit (5) from the dividend, add it to 102, then carry on: 1025 / 661

On to step 7:
1025 divided by 661 is 1 with a remainder of 364.
The next digit of our result is 1. 
Result so far: 13101.0
Deduct 661 from 1025 and we're left with 364.
Bring next digit (0) of the dividend behind the 364 and repeat the process: 3640 / 661

On to step 8:
When dividing 3640 by 661, we get 5 with a remainder of 335.
Use 5 as the next digit of our solution. 
Result so far: 131015.0
Subtract 3305 from 3640 to get 335.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3350, and continue the process.

Moving on to step 9:
If we divide 3350 by 661, we get 5 and a remainder of 45.
Use 5 as the next digit of our solution. 
Result so far: 131015.5
Deduct 3305 from 3350 and we're left with 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Let's proceed to step 10:
661 goes into 450 0 times with a remainder of 450.
The number 0 becomes the next digit in our result. 
Result so far: 131015.5
If we subtract 0 from 450, we get 450.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4500, and continue the process.

Going ahead to step 11:
The number 661 fits into 4500 6 times, leaving a remainder of 534.
Use 6 as the next digit of our solution. 
Result so far: 131015.506
The remainder is 534 after subtracting 3966 from 4500.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5340, and continue the process.

Going ahead to step 12:
661 can be fit into 5340 8 times, resulting in a remainder of 52.
Put 8 as the next digit of the answer. 
Result so far: 131015.5068
If we take 5288 away from 5340, we end up with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Going ahead to step 13:
520 divided by 661 is 0 with a remainder of 520.
Record the quotient 0 as the next digit in the result. 
Result so far: 131015.5068
Subtract 0 from 520 to get 520.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5200, and continue the process.

On to step 14:
661 goes into 5200 7 times with a remainder of 573.
Use 7 as the next digit of our solution. 
Result so far: 131015.506807
Subtracting 4627 from 5200 leaves us with 573.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5730, and continue the process.

Step 15:
661 can be fit into 5730 8 times, resulting in a remainder of 442.
Use 8 as the next digit of our solution. 
Result so far: 131015.5068078
If we take 5288 away from 5730, we end up with 442.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4420, and continue the process.

Let's proceed to step 16:
If we divide 4420 by 661, we get 6 and a remainder of 454.
Use 6 as the next digit of our solution. 
Result so far: 131015.50680786
If we take 3966 away from 4420, we end up with 454.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4540, and continue the process.

The final outcome is 131015.50680786, with a leftover of 4.54e-07.