We're dividing 10281172 by 21 
We want to figure out the number of times 10281172 can be divided by 21.

Going ahead to step 1:
If we divide 1 by 21, we get 0 and a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Take the next digit (0) from the dividend and append it to 1, then repeat: 10 / 21

Moving on to step 2:
When dividing 10 by 21, we get 0 with a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 10, we end up with 10.
Grab the next digit (2) from the dividend, add it to 10, then carry on: 102 / 21

On to step 3:
When dividing 102 by 21, we get 4 with a remainder of 18.
Write down 4 as next digit of the result. 
Result so far: 4.0
Subtract 84 from 102 to get 18.
Bring next digit (8) of the dividend behind the 18 and repeat the process: 188 / 21

Let's proceed to step 4:
188 divided by 21 is 8 with a remainder of 20.
The next digit of our result is 8. 
Result so far: 48.0
The remainder is 20 after subtracting 168 from 188.
Append the next digit (1) from the dividend to 20 and continue with: 201 / 21

Step 5:
The number 21 fits into 201 9 times, leaving a remainder of 12.
Put 9 as the next digit of the answer. 
Result so far: 489.0
Deduct 189 from 201 and we're left with 12.
Take the next digit (1) from the dividend and append it to 12, then repeat: 121 / 21

Advancing to step 6:
121 divided by 21 is 5 with a remainder of 16.
The number 5 becomes the next digit in our result. 
Result so far: 4895.0
Deduct 105 from 121 and we're left with 16.
Take the next digit (7) from the dividend and append it to 16, then repeat: 167 / 21

Let's proceed to step 7:
If we divide 167 by 21, we get 7 and a remainder of 20.
The number 7 becomes the next digit in our result. 
Result so far: 48957.0
Deduct 147 from 167 and we're left with 20.
Include the next digit (2) from the dividend after 20, then repeat: 202 / 21

Step 8:
The number 21 fits into 202 9 times, leaving a remainder of 13.
Put 9 as the next digit of the answer. 
Result so far: 489579.0
Deduct 189 from 202 and we're left 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.

Going ahead to step 9:
When dividing 130 by 21, we get 6 with a remainder of 4.
Use 6 as the next digit of our solution. 
Result so far: 489579.6
Subtracting 126 from 130 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Step 10:
If we divide 40 by 21, we get 1 and a remainder of 19.
Put 1 as the next digit of the answer. 
Result so far: 489579.61
Deduct 21 from 40 and we're left with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Step 11:
21 can be fit into 190 9 times, resulting in a remainder of 1.
Record the quotient 9 as the next digit in the result. 
Result so far: 489579.619
Subtract 189 from 190 to get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 12:
When dividing 10 by 21, we get 0 with a remainder of 10.
Use 0 as the next digit of our solution. 
Result so far: 489579.619
If we take 0 away from 10, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Let's proceed to step 13:
If we divide 100 by 21, we get 4 and a remainder of 16.
Put 4 as the next digit of the answer. 
Result so far: 489579.61904
If we take 84 away from 100, we end up 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.

Moving on to step 14:
21 goes into 160 7 times with a remainder of 13.
The number 7 becomes the next digit in our result. 
Result so far: 489579.619047
The remainder is 13 after subtracting 147 from 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Step 15:
21 can be fit into 130 6 times, resulting in a remainder of 4.
Put 6 as the next digit of the answer. 
Result so far: 489579.6190476
If we take 126 away from 130, we end up with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Going ahead to step 16:
40 divided by 21 is 1 with a remainder of 19.
The next digit of our result is 1. 
Result so far: 489579.61904761
If we subtract 21 from 40, we get 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

After the division, we end up with 489579.61904761 and a remainder of 1.9e-08.