We look at the division of 21623138 by 243 
Let's see how many times 243 fits into 21623138.

Advancing to step 1:
243 can be fit into 2 0 times, resulting in a remainder of 2.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 2 and we're left with 2.
Include the next digit (1) from the dividend after 2, then repeat: 21 / 243

Let's proceed to step 2:
243 goes into 21 0 times with a remainder of 21.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 21, we end up with 21.
Grab the next digit (6) from the dividend, add it to 21, then carry on: 216 / 243

Step 3:
When dividing 216 by 243, we get 0 with a remainder of 216.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 216 after subtracting 0 from 216.
Take the next digit (2) from the dividend and append it to 216, then repeat: 2162 / 243

Moving on to step 4:
243 can be fit into 2162 8 times, resulting in a remainder of 218.
Record the quotient 8 as the next digit in the result. 
Result so far: 8.0
If we take 1944 away from 2162, we end up with 218.
Include the next digit (3) from the dividend after 218, then repeat: 2183 / 243

Moving on to step 5:
2183 divided by 243 is 8 with a remainder of 239.
Record the quotient 8 as the next digit in the result. 
Result so far: 88.0
Subtracting 1944 from 2183 leaves us with 239.
Append the next digit (1) from the dividend to 239 and continue with: 2391 / 243

Advancing to step 6:
2391 divided by 243 is 9 with a remainder of 204.
Use 9 as the next digit of our solution. 
Result so far: 889.0
If we take 2187 away from 2391, we end up with 204.
Append the next digit (3) from the dividend to 204 and continue with: 2043 / 243

On to step 7:
243 can be fit into 2043 8 times, resulting in a remainder of 99.
Record the quotient 8 as the next digit in the result. 
Result so far: 8898.0
Subtracting 1944 from 2043 leaves us with 99.
Grab the next digit (8) from the dividend, add it to 99, then carry on: 998 / 243

Moving on to step 8:
The number 243 fits into 998 4 times, leaving a remainder of 26.
The number 4 becomes the next digit in our result. 
Result so far: 88984.0
Subtract 972 from 998 to get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Moving on to step 9:
243 goes into 260 1 times with a remainder of 17.
Put 1 as the next digit of the answer. 
Result so far: 88984.1
If we take 243 away from 260, 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.

Let's proceed to step 10:
If we divide 170 by 243, we get 0 and a remainder of 170.
Use 0 as the next digit of our solution. 
Result so far: 88984.1
Subtracting 0 from 170 leaves us with 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1700, and continue the process.

On to step 11:
If we divide 1700 by 243, we get 6 and a remainder of 242.
Write down 6 as next digit of the result. 
Result so far: 88984.106
If we take 1458 away from 1700, we end up with 242.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2420, and continue the process.

Advancing to step 12:
243 goes into 2420 9 times with a remainder of 233.
Use 9 as the next digit of our solution. 
Result so far: 88984.1069
Deduct 2187 from 2420 and we're left with 233.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2330, and continue the process.

On to step 13:
When dividing 2330 by 243, we get 9 with a remainder of 143.
Use 9 as the next digit of our solution. 
Result so far: 88984.10699
If we subtract 2187 from 2330, we get 143.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1430, and continue the process.

Our division results in 88984.10699 with a remaining 0.000143.