Let's divide 436817 by 21
We want to figure out the number of times 436817 can be divided by 21.

Advancing to step 1:
When dividing 4 by 21, we get 0 with a remainder of 4.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Bring next digit (3) of the dividend behind the 4 and repeat the process: 43 / 21

Going ahead to step 2:
43 divided by 21 is 2 with a remainder of 1.
Put 2 as the next digit of the answer. 
Result so far: 2.0
If we subtract 42 from 43, we get 1.
Take the next digit (6) from the dividend and append it to 1, then repeat: 16 / 21

Going ahead to step 3:
When dividing 16 by 21, we get 0 with a remainder of 16.
Put 0 as the next digit of the answer. 
Result so far: 20.0
Subtract 0 from 16 to get 16.
Take the next digit (8) from the dividend and append it to 16, then repeat: 168 / 21

Let's proceed to step 4:
21 goes into 168 8 times with a remainder of 0.
Use 8 as the next digit of our solution. 
Result so far: 208.0
If we subtract 168 from 168, we get 0.
Append the next digit (1) from the dividend to 0 and continue with: 1 / 21

Going ahead to step 5:
21 goes into 1 0 times with a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 2080.0
Subtract 0 from 1 to get 1.
Append the next digit (7) from the dividend to 1 and continue with: 17 / 21

Moving on to step 6:
The number 21 fits into 17 0 times, leaving a remainder of 17.
Record the quotient 0 as the next digit in the result. 
Result so far: 20800.0
Deduct 0 from 17 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.

Going ahead to step 7:
21 can be fit into 170 8 times, resulting in a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 20800.8
Deduct 168 from 170 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 8:
If we divide 20 by 21, we get 0 and a remainder of 20.
The next digit of our result is 0. 
Result so far: 20800.8
If we take 0 away from 20, we end up 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.

Step 9:
21 can be fit into 200 9 times, resulting in a remainder of 11.
The next digit of our result is 9. 
Result so far: 20800.809
The remainder is 11 after subtracting 189 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

On to step 10:
If we divide 110 by 21, we get 5 and a remainder of 5.
Write down 5 as next digit of the result. 
Result so far: 20800.8095
Subtracting 105 from 110 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 11:
50 divided by 21 is 2 with a remainder of 8.
The number 2 becomes the next digit in our result. 
Result so far: 20800.80952
Deduct 42 from 50 and we're left 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.

Step 12:
When dividing 80 by 21, we get 3 with a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 20800.809523
If we subtract 63 from 80, we get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Advancing to step 13:
170 divided by 21 is 8 with a remainder of 2.
Record the quotient 8 as the next digit in the result. 
Result so far: 20800.8095238
If we take 168 away from 170, we end up with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 14:
21 can be fit into 20 0 times, resulting in a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 20800.8095238
Subtract 0 from 20 to 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.

The final outcome is 20800.8095238, with a leftover of 2e-08.