We look at the division of 421638 by 23 
Our goal is to divide 421638 by 23.

On to step 1:
23 can be fit into 4 0 times, resulting in a remainder of 4.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Fetch the next digit (2) from the dividend, attach it to 4 and continue: 42 / 23

Step 2:
The number 23 fits into 42 1 times, leaving a remainder of 19.
The next digit of our result is 1. 
Result so far: 1.0
If we subtract 23 from 42, we get 19.
Include the next digit (1) from the dividend after 19, then repeat: 191 / 23

Moving on to step 3:
If we divide 191 by 23, we get 8 and a remainder of 7.
Put 8 as the next digit of the answer. 
Result so far: 18.0
Deduct 184 from 191 and we're left with 7.
Take the next digit (6) from the dividend and append it to 7, then repeat: 76 / 23

On to step 4:
23 goes into 76 3 times with a remainder of 7.
The next digit of our result is 3. 
Result so far: 183.0
Subtracting 69 from 76 leaves us with 7.
Append the next digit (3) from the dividend to 7 and continue with: 73 / 23

Going ahead to step 5:
If we divide 73 by 23, we get 3 and a remainder of 4.
Put 3 as the next digit of the answer. 
Result so far: 1833.0
Subtracting 69 from 73 leaves us with 4.
Grab the next digit (8) from the dividend, add it to 4, then carry on: 48 / 23

Going ahead to step 6:
The number 23 fits into 48 2 times, leaving a remainder of 2.
Use 2 as the next digit of our solution. 
Result so far: 18332.0
If we take 46 away from 48, 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.

Let's proceed to step 7:
When dividing 20 by 23, we get 0 with a remainder of 20.
The next digit of our result is 0. 
Result so far: 18332.0
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.

Let's proceed to step 8:
23 goes into 200 8 times with a remainder of 16.
The number 8 becomes the next digit in our result. 
Result so far: 18332.08
Subtracting 184 from 200 leaves us with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

On to step 9:
160 divided by 23 is 6 with a remainder of 22.
Use 6 as the next digit of our solution. 
Result so far: 18332.086
Subtracting 138 from 160 leaves us with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Let's proceed to step 10:
When dividing 220 by 23, we get 9 with a remainder of 13.
The next digit of our result is 9. 
Result so far: 18332.0869
If we take 207 away from 220, we end up with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Let's proceed to step 11:
23 can be fit into 130 5 times, resulting in a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 18332.08695
The remainder is 15 after subtracting 115 from 130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Let's proceed to step 12:
150 divided by 23 is 6 with a remainder of 12.
Use 6 as the next digit of our solution. 
Result so far: 18332.086956
The remainder is 12 after subtracting 138 from 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 13:
23 goes into 120 5 times with a remainder of 5.
Write down 5 as next digit of the result. 
Result so far: 18332.0869565
The remainder is 5 after subtracting 115 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Let's proceed to step 14:
When dividing 50 by 23, we get 2 with a remainder of 4.
The next digit of our result is 2. 
Result so far: 18332.08695652
If we subtract 46 from 50, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

The quotient of the division is 18332.08695652, and the remainder is 4e-09.