We divide 287451 by 21
Our goal is to divide 287451 by 21.

Advancing to step 1:
When dividing 2 by 21, we get 0 with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Bring next digit (8) of the dividend behind the 2 and repeat the process: 28 / 21

Moving on to step 2:
28 divided by 21 is 1 with a remainder of 7.
Write down 1 as next digit of the result. 
Result so far: 1.0
Deduct 21 from 28 and we're left with 7.
Bring next digit (7) of the dividend behind the 7 and repeat the process: 77 / 21

Step 3:
If we divide 77 by 21, we get 3 and a remainder of 14.
The next digit of our result is 3. 
Result so far: 13.0
Subtracting 63 from 77 leaves us with 14.
Fetch the next digit (4) from the dividend, attach it to 14 and continue: 144 / 21

On to step 4:
When dividing 144 by 21, we get 6 with a remainder of 18.
The number 6 becomes the next digit in our result. 
Result so far: 136.0
Subtract 126 from 144 to get 18.
Include the next digit (5) from the dividend after 18, then repeat: 185 / 21

Step 5:
When dividing 185 by 21, we get 8 with a remainder of 17.
Record the quotient 8 as the next digit in the result. 
Result so far: 1368.0
Subtracting 168 from 185 leaves us with 17.
Fetch the next digit (1) from the dividend, attach it to 17 and continue: 171 / 21

On to step 6:
When dividing 171 by 21, we get 8 with a remainder of 3.
The next digit of our result is 8. 
Result so far: 13688.0
Subtract 168 from 171 to get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Going ahead to step 7:
If we divide 30 by 21, we get 1 and a remainder of 9.
Record the quotient 1 as the next digit in the result. 
Result so far: 13688.1
Subtract 21 from 30 to get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Moving on to step 8:
The number 21 fits into 90 4 times, leaving a remainder of 6.
Put 4 as the next digit of the answer. 
Result so far: 13688.14
If we subtract 84 from 90, we get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 9:
21 goes into 60 2 times with a remainder of 18.
The next digit of our result is 2. 
Result so far: 13688.142
Subtracting 42 from 60 leaves us with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Advancing to step 10:
If we divide 180 by 21, we get 8 and a remainder of 12.
The number 8 becomes the next digit in our result. 
Result so far: 13688.1428
Subtracting 168 from 180 leaves us with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Advancing to step 11:
The number 21 fits into 120 5 times, leaving a remainder of 15.
Put 5 as the next digit of the answer. 
Result so far: 13688.14285
If we subtract 105 from 120, we get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Moving on to step 12:
150 divided by 21 is 7 with a remainder of 3.
The next digit of our result is 7. 
Result so far: 13688.142857
Subtracting 147 from 150 leaves us with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 13:
21 can be fit into 30 1 times, resulting in a remainder of 9.
Record the quotient 1 as the next digit in the result. 
Result so far: 13688.1428571
If we subtract 21 from 30, we get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Let's proceed to step 14:
21 goes into 90 4 times with a remainder of 6.
The number 4 becomes the next digit in our result. 
Result so far: 13688.14285714
Subtracting 84 from 90 leaves us with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

The quotient of the division is 13688.14285714, and the remainder is 6e-09.