We divide 435221 by 21
We want to figure out the number of times 435221 can be divided by 21.

Moving on to step 1:
If we divide 4 by 21, we get 0 and a remainder of 4.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 4 after subtracting 0 from 4.
Fetch the next digit (3) from the dividend, attach it to 4 and continue: 43 / 21

Advancing to step 2:
21 goes into 43 2 times with a remainder of 1.
The next digit of our result is 2. 
Result so far: 2.0
The remainder is 1 after subtracting 42 from 43.
Take the next digit (5) from the dividend and append it to 1, then repeat: 15 / 21

Going ahead to step 3:
21 can be fit into 15 0 times, resulting in a remainder of 15.
The number 0 becomes the next digit in our result. 
Result so far: 20.0
Subtracting 0 from 15 leaves us with 15.
Bring next digit (2) of the dividend behind the 15 and repeat the process: 152 / 21

Going ahead to step 4:
The number 21 fits into 152 7 times, leaving a remainder of 5.
Record the quotient 7 as the next digit in the result. 
Result so far: 207.0
The remainder is 5 after subtracting 147 from 152.
Take the next digit (2) from the dividend and append it to 5, then repeat: 52 / 21

Going ahead to step 5:
52 divided by 21 is 2 with a remainder of 10.
Write down 2 as next digit of the result. 
Result so far: 2072.0
If we take 42 away from 52, we end up with 10.
Grab the next digit (1) from the dividend, add it to 10, then carry on: 101 / 21

On to step 6:
21 can be fit into 101 4 times, resulting in a remainder of 17.
Put 4 as the next digit of the answer. 
Result so far: 20724.0
Deduct 84 from 101 and we're left with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Let's proceed to step 7:
21 can be fit into 170 8 times, resulting in a remainder of 2.
Put 8 as the next digit of the answer. 
Result so far: 20724.8
Subtract 168 from 170 to get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 8:
When dividing 20 by 21, we get 0 with a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 20724.8
Deduct 0 from 20 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 9:
21 can be fit into 200 9 times, resulting in a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 20724.809
If we take 189 away from 200, we end up with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Moving on to step 10:
When dividing 110 by 21, we get 5 with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 20724.8095
The remainder is 5 after subtracting 105 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Advancing to step 11:
21 goes into 50 2 times with a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 20724.80952
If we take 42 away from 50, we end up with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Going ahead to step 12:
21 goes into 80 3 times with a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 20724.809523
If we take 63 away from 80, we end up with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Step 13:
The number 21 fits into 170 8 times, leaving a remainder of 2.
Put 8 as the next digit of the answer. 
Result so far: 20724.8095238
Subtract 168 from 170 to get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Let's proceed to step 14:
21 goes into 20 0 times with a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 20724.8095238
If we subtract 0 from 20, we get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

In conclusion, the division gives 20724.8095238 with a balance of 2e-08.