215558 divided by 21 
We want to divide 215558 by 21.

On to step 1:
When dividing 2 by 21, we get 0 with a remainder of 2.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 21

Moving on to step 2:
The number 21 fits into 21 1 times, leaving a remainder of 0.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Subtract 21 from 21 to get 0.
Bring next digit (5) of the dividend behind the 0 and repeat the process: 5 / 21

On to step 3:
5 divided by 21 is 0 with a remainder of 5.
Put 0 as the next digit of the answer. 
Result so far: 10.0
If we subtract 0 from 5, we get 5.
Take the next digit (5) from the dividend and append it to 5, then repeat: 55 / 21

Moving on to step 4:
If we divide 55 by 21, we get 2 and a remainder of 13.
Put 2 as the next digit of the answer. 
Result so far: 102.0
Subtract 42 from 55 to get 13.
Fetch the next digit (5) from the dividend, attach it to 13 and continue: 135 / 21

On to step 5:
21 goes into 135 6 times with a remainder of 9.
The number 6 becomes the next digit in our result. 
Result so far: 1026.0
Subtracting 126 from 135 leaves us with 9.
Fetch the next digit (8) from the dividend, attach it to 9 and continue: 98 / 21

Let's proceed to step 6:
21 can be fit into 98 4 times, resulting in a remainder of 14.
Use 4 as the next digit of our solution. 
Result so far: 10264.0
Deduct 84 from 98 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.

Going ahead to step 7:
140 divided by 21 is 6 with a remainder of 14.
The next digit of our result is 6. 
Result so far: 10264.6
If we subtract 126 from 140, we 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:
21 can be fit into 140 6 times, resulting in a remainder of 14.
Use 6 as the next digit of our solution. 
Result so far: 10264.66
Subtracting 126 from 140 leaves us 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 10264.66 with a remaining 0.014.