We're dividing 432509 by 21 
We're looking to find how many times 21 goes into 432509.

Going ahead to step 1:
The number 21 fits into 4 0 times, leaving a remainder of 4.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 4 after subtracting 0 from 4.
Append the next digit (3) from the dividend to 4 and continue with: 43 / 21

Let's proceed to step 2:
The number 21 fits into 43 2 times, leaving a remainder of 1.
Write down 2 as next digit of the result. 
Result so far: 2.0
Subtracting 42 from 43 leaves us with 1.
Grab the next digit (2) from the dividend, add it to 1, then carry on: 12 / 21

Let's proceed to step 3:
21 goes into 12 0 times with a remainder of 12.
Record the quotient 0 as the next digit in the result. 
Result so far: 20.0
Subtracting 0 from 12 leaves us with 12.
Include the next digit (5) from the dividend after 12, then repeat: 125 / 21

Going ahead to step 4:
125 divided by 21 is 5 with a remainder of 20.
Use 5 as the next digit of our solution. 
Result so far: 205.0
The remainder is 20 after subtracting 105 from 125.
Grab the next digit (0) from the dividend, add it to 20, then carry on: 200 / 21

Going ahead to step 5:
When dividing 200 by 21, we get 9 with a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 2059.0
Subtracting 189 from 200 leaves us with 11.
Append the next digit (9) from the dividend to 11 and continue with: 119 / 21

Advancing to step 6:
21 can be fit into 119 5 times, resulting in a remainder of 14.
Put 5 as the next digit of the answer. 
Result so far: 20595.0
Subtracting 105 from 119 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.

Moving on to step 7:
When dividing 140 by 21, we get 6 with a remainder of 14.
Record the quotient 6 as the next digit in the result. 
Result so far: 20595.6
If we take 126 away from 140, we end up 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.

Moving on to step 8:
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: 20595.66
The remainder is 14 after subtracting 126 from 140.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

The quotient of the division is 20595.66, and the remainder is 0.014.