We're dividing 657966 by 21 
We're looking to find how many times 21 goes into 657966.

Advancing to step 1:
21 can be fit into 6 0 times, resulting in a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Take the next digit (5) from the dividend and append it to 6, then repeat: 65 / 21

Moving on to step 2:
When dividing 65 by 21, we get 3 with a remainder of 2.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
Subtract 63 from 65 to get 2.
Take the next digit (7) from the dividend and append it to 2, then repeat: 27 / 21

Advancing to step 3:
If we divide 27 by 21, we get 1 and a remainder of 6.
Record the quotient 1 as the next digit in the result. 
Result so far: 31.0
Subtract 21 from 27 to get 6.
Grab the next digit (9) from the dividend, add it to 6, then carry on: 69 / 21

Step 4:
21 goes into 69 3 times with a remainder of 6.
The next digit of our result is 3. 
Result so far: 313.0
Subtract 63 from 69 to get 6.
Fetch the next digit (6) from the dividend, attach it to 6 and continue: 66 / 21

Let's proceed to step 5:
The number 21 fits into 66 3 times, leaving a remainder of 3.
Use 3 as the next digit of our solution. 
Result so far: 3133.0
Subtracting 63 from 66 leaves us with 3.
Fetch the next digit (6) from the dividend, attach it to 3 and continue: 36 / 21

Advancing to step 6:
36 divided by 21 is 1 with a remainder of 15.
Use 1 as the next digit of our solution. 
Result so far: 31331.0
Subtracting 21 from 36 leaves us 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.

Advancing to step 7:
If we divide 150 by 21, we get 7 and a remainder of 3.
The next digit of our result is 7. 
Result so far: 31331.7
If we subtract 147 from 150, we 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.

Advancing to step 8:
If we divide 30 by 21, we get 1 and a remainder of 9.
The next digit of our result is 1. 
Result so far: 31331.71
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.

Moving on to step 9:
90 divided by 21 is 4 with a remainder of 6.
Record the quotient 4 as the next digit in the result. 
Result so far: 31331.714
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.

Moving on to step 10:
21 goes into 60 2 times with a remainder of 18.
Record the quotient 2 as the next digit in the result. 
Result so far: 31331.7142
If we subtract 42 from 60, we 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.

Let's proceed to step 11:
The number 21 fits into 180 8 times, leaving a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 31331.71428
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.

Let's proceed to step 12:
When dividing 120 by 21, we get 5 with a remainder of 15.
The number 5 becomes the next digit in our result. 
Result so far: 31331.714285
Subtract 105 from 120 to 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.

On to step 13:
When dividing 150 by 21, we get 7 with a remainder of 3.
The next digit of our result is 7. 
Result so far: 31331.7142857
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.

Going ahead to step 14:
When dividing 30 by 21, we get 1 with a remainder of 9.
Record the quotient 1 as the next digit in the result. 
Result so far: 31331.71428571
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.

The final outcome is 31331.71428571, with a leftover of 9e-09.