490730 ÷ 21 
We want to figure out the number of times 490730 can be divided by 21.

Advancing to step 1:
When dividing 4 by 21, we get 0 with a remainder of 4.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 4 and we're left with 4.
Grab the next digit (9) from the dividend, add it to 4, then carry on: 49 / 21

Step 2:
49 divided by 21 is 2 with a remainder of 7.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtract 42 from 49 to get 7.
Append the next digit (0) from the dividend to 7 and continue with: 70 / 21

Moving on to step 3:
21 goes into 70 3 times with a remainder of 7.
The number 3 becomes the next digit in our result. 
Result so far: 23.0
If we take 63 away from 70, we end up with 7.
Take the next digit (7) from the dividend and append it to 7, then repeat: 77 / 21

Advancing to step 4:
77 divided by 21 is 3 with a remainder of 14.
The next digit of our result is 3. 
Result so far: 233.0
Subtract 63 from 77 to get 14.
Fetch the next digit (3) from the dividend, attach it to 14 and continue: 143 / 21

Advancing to step 5:
When dividing 143 by 21, we get 6 with a remainder of 17.
Use 6 as the next digit of our solution. 
Result so far: 2336.0
Subtract 126 from 143 to get 17.
Grab the next digit (0) from the dividend, add it to 17, then carry on: 170 / 21

Let's proceed to step 6:
21 can be fit into 170 8 times, resulting in a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 23368.0
Subtracting 168 from 170 leaves us 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.

Advancing to step 7:
If we divide 20 by 21, we get 0 and a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 23368.0
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.

Step 8:
21 goes into 200 9 times with a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 23368.09
If we subtract 189 from 200, we get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Step 9:
When dividing 110 by 21, we get 5 with a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 23368.095
Subtracting 105 from 110 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 10:
When dividing 50 by 21, we get 2 with a remainder of 8.
The next digit of our result is 2. 
Result so far: 23368.0952
Deduct 42 from 50 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Going ahead to step 11:
21 goes into 80 3 times with a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 23368.09523
Subtracting 63 from 80 leaves us 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.

Going ahead to step 12:
21 can be fit into 170 8 times, resulting in a remainder of 2.
Record the quotient 8 as the next digit in the result. 
Result so far: 23368.095238
Subtracting 168 from 170 leaves us 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 13:
20 divided by 21 is 0 with a remainder of 20.
Put 0 as the next digit of the answer. 
Result so far: 23368.095238
The remainder is 20 after subtracting 0 from 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 14:
The number 21 fits into 200 9 times, leaving a remainder of 11.
The next digit of our result is 9. 
Result so far: 23368.09523809
Subtract 189 from 200 to get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

The final result is 23368.09523809 with a remainder of 1.1e-08.