We look at the division of 881636 by 21 
Let's see how many times 21 fits into 881636.

Step 1:
21 can be fit into 8 0 times, resulting in 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 (8) from the dividend and append it to 8, then repeat: 88 / 21

Moving on to step 2:
88 divided by 21 is 4 with a remainder of 4.
The next digit of our result is 4. 
Result so far: 4.0
If we subtract 84 from 88, we get 4.
Fetch the next digit (1) from the dividend, attach it to 4 and continue: 41 / 21

Moving on to step 3:
21 can be fit into 41 1 times, resulting in a remainder of 20.
The number 1 becomes the next digit in our result. 
Result so far: 41.0
If we subtract 21 from 41, we get 20.
Bring next digit (6) of the dividend behind the 20 and repeat the process: 206 / 21

Let's proceed to step 4:
If we divide 206 by 21, we get 9 and a remainder of 17.
Use 9 as the next digit of our solution. 
Result so far: 419.0
Subtract 189 from 206 to get 17.
Grab the next digit (3) from the dividend, add it to 17, then carry on: 173 / 21

Step 5:
If we divide 173 by 21, we get 8 and a remainder of 5.
Record the quotient 8 as the next digit in the result. 
Result so far: 4198.0
Deduct 168 from 173 and we're left with 5.
Bring next digit (6) of the dividend behind the 5 and repeat the process: 56 / 21

Step 6:
When dividing 56 by 21, we get 2 with a remainder of 14.
The next digit of our result is 2. 
Result so far: 41982.0
Subtract 42 from 56 to get 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Going ahead to step 7:
If we divide 140 by 21, we get 6 and a remainder of 14.
Put 6 as the next digit of the answer. 
Result so far: 41982.6
Subtract 126 from 140 to get 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Advancing to step 8:
If we divide 140 by 21, we get 6 and a remainder of 14.
The number 6 becomes the next digit in our result. 
Result so far: 41982.66
Deduct 126 from 140 and we're left with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Our division results in 41982.66 with a remaining 0.014.