216721 divided by 2 
We want to figure out the number of times 216721 can be divided by 2.

Step 1:
If we divide 2 by 2, we get 1 and a remainder of 0.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we subtract 2 from 2, we get 0.
Fetch the next digit (1) from the dividend, attach it to 0 and continue: 1 / 2

Let's proceed to step 2:
1 divided by 2 is 0 with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 10.0
If we subtract 0 from 1, we get 1.
Bring next digit (6) of the dividend behind the 1 and repeat the process: 16 / 2

Let's proceed to step 3:
2 can be fit into 16 8 times, resulting in a remainder of 0.
The number 8 becomes the next digit in our result. 
Result so far: 108.0
Subtract 16 from 16 to get 0.
Fetch the next digit (7) from the dividend, attach it to 0 and continue: 7 / 2

Advancing to step 4:
The number 2 fits into 7 3 times, leaving a remainder of 1.
Write down 3 as next digit of the result. 
Result so far: 1083.0
Subtract 6 from 7 to get 1.
Append the next digit (2) from the dividend to 1 and continue with: 12 / 2

Going ahead to step 5:
The number 2 fits into 12 6 times, leaving a remainder of 0.
The next digit of our result is 6. 
Result so far: 10836.0
If we subtract 12 from 12, we get 0.
Take the next digit (1) from the dividend and append it to 0, then repeat: 1 / 2

On to step 6:
The number 2 fits into 1 0 times, leaving a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 108360.0
If we subtract 0 from 1, we get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Step 7:
2 can be fit into 10 5 times, resulting in a remainder of 0.
The next digit of our result is 5. 
Result so far: 108360.5
Subtract 10 from 10 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.

Step 8:
0 divided by 2 is 0 with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 108360.5
Deduct 0 from 0 and we're left 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.

Let's proceed to step 9:
2 can be fit into 0 0 times, resulting in a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 108360.5
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 quotient of the division is 108360.5, and the remainder is 0.0.