128643 divided by 15 
We want to figure out the number of times 128643 can be divided by 15.

On to step 1:
The number 15 fits into 1 0 times, leaving a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Include the next digit (2) from the dividend after 1, then repeat: 12 / 15

Going ahead to step 2:
15 goes into 12 0 times with a remainder of 12.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 12 and we're left with 12.
Grab the next digit (8) from the dividend, add it to 12, then carry on: 128 / 15

On to step 3:
The number 15 fits into 128 8 times, leaving a remainder of 8.
Record the quotient 8 as the next digit in the result. 
Result so far: 8.0
If we take 120 away from 128, we end up with 8.
Take the next digit (6) from the dividend and append it to 8, then repeat: 86 / 15

Advancing to step 4:
When dividing 86 by 15, we get 5 with a remainder of 11.
Record the quotient 5 as the next digit in the result. 
Result so far: 85.0
Deduct 75 from 86 and we're left with 11.
Take the next digit (4) from the dividend and append it to 11, then repeat: 114 / 15

Step 5:
15 can be fit into 114 7 times, resulting in a remainder of 9.
Write down 7 as next digit of the result. 
Result so far: 857.0
If we subtract 105 from 114, we get 9.
Include the next digit (3) from the dividend after 9, then repeat: 93 / 15

Let's proceed to step 6:
93 divided by 15 is 6 with a remainder of 3.
The number 6 becomes the next digit in our result. 
Result so far: 8576.0
Deduct 90 from 93 and we're left with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 7:
30 divided by 15 is 2 with a remainder of 0.
The next digit of our result is 2. 
Result so far: 8576.2
Subtracting 30 from 30 leaves us 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.

Step 8:
When dividing 0 by 15, we get 0 with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 8576.2
Subtracting 0 from 0 leaves us 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.

Advancing to step 9:
15 can be fit into 0 0 times, resulting in a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 8576.2
Subtract 0 from 0 to 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 8576.2, with a leftover of 0.0.