We're dividing 21396612 by 809 
Let's see how many times 809 fits into 21396612.

Going ahead to step 1:
2 divided by 809 is 0 with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Grab the next digit (1) from the dividend, add it to 2, then carry on: 21 / 809

On to step 2:
When dividing 21 by 809, we get 0 with a remainder of 21.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 21 leaves us with 21.
Take the next digit (3) from the dividend and append it to 21, then repeat: 213 / 809

Moving on to step 3:
809 goes into 213 0 times with a remainder of 213.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 213 to get 213.
Append the next digit (9) from the dividend to 213 and continue with: 2139 / 809

Going ahead to step 4:
If we divide 2139 by 809, we get 2 and a remainder of 521.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtract 1618 from 2139 to get 521.
Include the next digit (6) from the dividend after 521, then repeat: 5216 / 809

Step 5:
If we divide 5216 by 809, we get 6 and a remainder of 362.
Use 6 as the next digit of our solution. 
Result so far: 26.0
If we subtract 4854 from 5216, we get 362.
Fetch the next digit (6) from the dividend, attach it to 362 and continue: 3626 / 809

On to step 6:
3626 divided by 809 is 4 with a remainder of 390.
Put 4 as the next digit of the answer. 
Result so far: 264.0
Deduct 3236 from 3626 and we're left with 390.
Grab the next digit (1) from the dividend, add it to 390, then carry on: 3901 / 809

On to step 7:
3901 divided by 809 is 4 with a remainder of 665.
Use 4 as the next digit of our solution. 
Result so far: 2644.0
Subtracting 3236 from 3901 leaves us with 665.
Take the next digit (2) from the dividend and append it to 665, then repeat: 6652 / 809

Step 8:
When dividing 6652 by 809, we get 8 with a remainder of 180.
Write down 8 as next digit of the result. 
Result so far: 26448.0
If we subtract 6472 from 6652, we get 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1800, and continue the process.

On to step 9:
If we divide 1800 by 809, we get 2 and a remainder of 182.
The next digit of our result is 2. 
Result so far: 26448.2
Subtracting 1618 from 1800 leaves us with 182.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1820, and continue the process.

Going ahead to step 10:
When dividing 1820 by 809, we get 2 with a remainder of 202.
Write down 2 as next digit of the result. 
Result so far: 26448.22
Subtract 1618 from 1820 to get 202.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2020, and continue the process.

After the division, we end up with 26448.22 and a remainder of 0.202.