We're dividing 64872 by 21 
We want to figure out the number of times 64872 can be divided by 21.

Step 1:
21 goes into 6 0 times with a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Bring next digit (4) of the dividend behind the 6 and repeat the process: 64 / 21

Let's proceed to step 2:
21 goes into 64 3 times with a remainder of 1.
Write down 3 as next digit of the result. 
Result so far: 3.0
If we subtract 63 from 64, we get 1.
Append the next digit (8) from the dividend to 1 and continue with: 18 / 21

Step 3:
If we divide 18 by 21, we get 0 and a remainder of 18.
Use 0 as the next digit of our solution. 
Result so far: 30.0
If we subtract 0 from 18, we get 18.
Include the next digit (7) from the dividend after 18, then repeat: 187 / 21

Going ahead to step 4:
When dividing 187 by 21, we get 8 with a remainder of 19.
Record the quotient 8 as the next digit in the result. 
Result so far: 308.0
If we take 168 away from 187, we end up with 19.
Bring next digit (2) of the dividend behind the 19 and repeat the process: 192 / 21

Step 5:
The number 21 fits into 192 9 times, leaving a remainder of 3.
Record the quotient 9 as the next digit in the result. 
Result so far: 3089.0
The remainder is 3 after subtracting 189 from 192.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Advancing to step 6:
The number 21 fits into 30 1 times, leaving a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 3089.1
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.

Moving on to step 7:
The number 21 fits into 90 4 times, leaving a remainder of 6.
The next digit of our result is 4. 
Result so far: 3089.14
The remainder is 6 after subtracting 84 from 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Going ahead to step 8:
The number 21 fits into 60 2 times, leaving a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 3089.142
Subtract 42 from 60 to get 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Going ahead to step 9:
When dividing 180 by 21, we get 8 with a remainder of 12.
Write down 8 as next digit of the result. 
Result so far: 3089.1428
Deduct 168 from 180 and we're left 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.

On to step 10:
21 goes into 120 5 times with a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 3089.14285
Deduct 105 from 120 and we're left with 15.
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 11:
The number 21 fits into 150 7 times, leaving a remainder of 3.
The next digit of our result is 7. 
Result so far: 3089.142857
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.

Step 12:
30 divided by 21 is 1 with a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 3089.1428571
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.

Advancing to step 13:
21 goes into 90 4 times with a remainder of 6.
The next digit of our result is 4. 
Result so far: 3089.14285714
Subtract 84 from 90 to 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.

The final outcome is 3089.14285714, with a leftover of 6e-09.