12869659 ÷ 864 
Our goal is to divide 12869659 by 864.

Let's proceed to step 1:
864 can be fit into 1 0 times, resulting in a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 864

Step 2:
If we divide 12 by 864, we get 0 and a remainder of 12.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 12 leaves us with 12.
Include the next digit (8) from the dividend after 12, then repeat: 128 / 864

On to step 3:
The number 864 fits into 128 0 times, leaving a remainder of 128.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 128 to get 128.
Fetch the next digit (6) from the dividend, attach it to 128 and continue: 1286 / 864

Going ahead to step 4:
864 goes into 1286 1 times with a remainder of 422.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
The remainder is 422 after subtracting 864 from 1286.
Include the next digit (9) from the dividend after 422, then repeat: 4229 / 864

Advancing to step 5:
4229 divided by 864 is 4 with a remainder of 773.
The number 4 becomes the next digit in our result. 
Result so far: 14.0
Subtracting 3456 from 4229 leaves us with 773.
Take the next digit (6) from the dividend and append it to 773, then repeat: 7736 / 864

Step 6:
7736 divided by 864 is 8 with a remainder of 824.
Write down 8 as next digit of the result. 
Result so far: 148.0
Subtract 6912 from 7736 to get 824.
Take the next digit (5) from the dividend and append it to 824, then repeat: 8245 / 864

Let's proceed to step 7:
If we divide 8245 by 864, we get 9 and a remainder of 469.
Use 9 as the next digit of our solution. 
Result so far: 1489.0
Subtracting 7776 from 8245 leaves us with 469.
Take the next digit (9) from the dividend and append it to 469, then repeat: 4699 / 864

Step 8:
When dividing 4699 by 864, we get 5 with a remainder of 379.
Record the quotient 5 as the next digit in the result. 
Result so far: 14895.0
If we take 4320 away from 4699, we end up with 379.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3790, and continue the process.

On to step 9:
The number 864 fits into 3790 4 times, leaving a remainder of 334.
The number 4 becomes the next digit in our result. 
Result so far: 14895.4
Subtracting 3456 from 3790 leaves us with 334.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3340, and continue the process.

Let's proceed to step 10:
If we divide 3340 by 864, we get 3 and a remainder of 748.
Put 3 as the next digit of the answer. 
Result so far: 14895.43
If we subtract 2592 from 3340, we get 748.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7480, and continue the process.

Let's proceed to step 11:
7480 divided by 864 is 8 with a remainder of 568.
Use 8 as the next digit of our solution. 
Result so far: 14895.438
If we subtract 6912 from 7480, we get 568.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5680, and continue the process.

Advancing to step 12:
864 goes into 5680 6 times with a remainder of 496.
The next digit of our result is 6. 
Result so far: 14895.4386
Subtract 5184 from 5680 to get 496.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4960, and continue the process.

Step 13:
When dividing 4960 by 864, we get 5 with a remainder of 640.
The next digit of our result is 5. 
Result so far: 14895.43865
Subtracting 4320 from 4960 leaves us with 640.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6400, and continue the process.

Let's proceed to step 14:
The number 864 fits into 6400 7 times, leaving a remainder of 352.
The next digit of our result is 7. 
Result so far: 14895.438657
Deduct 6048 from 6400 and we're left with 352.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3520, and continue the process.

Moving on to step 15:
864 goes into 3520 4 times with a remainder of 64.
The number 4 becomes the next digit in our result. 
Result so far: 14895.4386574
The remainder is 64 after subtracting 3456 from 3520.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Let's proceed to step 16:
640 divided by 864 is 0 with a remainder of 640.
The number 0 becomes the next digit in our result. 
Result so far: 14895.4386574
The remainder is 640 after subtracting 0 from 640.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6400, and continue the process.

The final outcome is 14895.4386574, with a leftover of 6.4e-07.