788343 divided by 21 
We want to figure out the number of times 788343 can be divided by 21.

Let's proceed to step 1:
The number 21 fits into 7 0 times, leaving a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 7 after subtracting 0 from 7.
Append the next digit (8) from the dividend to 7 and continue with: 78 / 21

Going ahead to step 2:
When dividing 78 by 21, we get 3 with a remainder of 15.
Use 3 as the next digit of our solution. 
Result so far: 3.0
The remainder is 15 after subtracting 63 from 78.
Bring next digit (8) of the dividend behind the 15 and repeat the process: 158 / 21

Step 3:
When dividing 158 by 21, we get 7 with a remainder of 11.
Use 7 as the next digit of our solution. 
Result so far: 37.0
Subtract 147 from 158 to get 11.
Take the next digit (3) from the dividend and append it to 11, then repeat: 113 / 21

Moving on to step 4:
21 can be fit into 113 5 times, resulting in a remainder of 8.
Record the quotient 5 as the next digit in the result. 
Result so far: 375.0
If we subtract 105 from 113, we get 8.
Fetch the next digit (4) from the dividend, attach it to 8 and continue: 84 / 21

Moving on to step 5:
The number 21 fits into 84 4 times, leaving a remainder of 0.
Record the quotient 4 as the next digit in the result. 
Result so far: 3754.0
The remainder is 0 after subtracting 84 from 84.
Include the next digit (3) from the dividend after 0, then repeat: 3 / 21

Moving on to step 6:
When dividing 3 by 21, we get 0 with a remainder of 3.
The next digit of our result is 0. 
Result so far: 37540.0
If we take 0 away from 3, we end up 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.

Going ahead to step 7:
30 divided by 21 is 1 with a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 37540.1
Subtracting 21 from 30 leaves us with 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:
If we divide 90 by 21, we get 4 and a remainder of 6.
The next digit of our result is 4. 
Result so far: 37540.14
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.

On to step 9:
21 can be fit into 60 2 times, resulting in a remainder of 18.
Write down 2 as next digit of the result. 
Result so far: 37540.142
If we take 42 away from 60, we end up 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:
The number 21 fits into 180 8 times, leaving a remainder of 12.
Write down 8 as next digit of the result. 
Result so far: 37540.1428
If we subtract 168 from 180, we get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 11:
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: 37540.14285
The remainder is 15 after subtracting 105 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Advancing to step 12:
When dividing 150 by 21, we get 7 with a remainder of 3.
The number 7 becomes the next digit in our result. 
Result so far: 37540.142857
Subtract 147 from 150 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 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: 37540.1428571
If we take 21 away from 30, we end up with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Step 14:
When dividing 90 by 21, we get 4 with a remainder of 6.
The next digit of our result is 4. 
Result so far: 37540.14285714
Deduct 84 from 90 and we're left 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 final outcome is 37540.14285714, with a leftover of 6e-09.