We divide 645664 by 66
Let's see how many times 66 fits into 645664.

Going ahead to step 1:
6 divided by 66 is 0 with a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Include the next digit (4) from the dividend after 6, then repeat: 64 / 66

Going ahead to step 2:
66 goes into 64 0 times with a remainder of 64.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 64 to get 64.
Include the next digit (5) from the dividend after 64, then repeat: 645 / 66

Moving on to step 3:
66 goes into 645 9 times with a remainder of 51.
The number 9 becomes the next digit in our result. 
Result so far: 9.0
The remainder is 51 after subtracting 594 from 645.
Fetch the next digit (6) from the dividend, attach it to 51 and continue: 516 / 66

Let's proceed to step 4:
66 goes into 516 7 times with a remainder of 54.
Use 7 as the next digit of our solution. 
Result so far: 97.0
The remainder is 54 after subtracting 462 from 516.
Take the next digit (6) from the dividend and append it to 54, then repeat: 546 / 66

Moving on to step 5:
If we divide 546 by 66, we get 8 and a remainder of 18.
The next digit of our result is 8. 
Result so far: 978.0
If we take 528 away from 546, we end up with 18.
Take the next digit (4) from the dividend and append it to 18, then repeat: 184 / 66

On to step 6:
184 divided by 66 is 2 with a remainder of 52.
The next digit of our result is 2. 
Result so far: 9782.0
Subtracting 132 from 184 leaves us with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

On to step 7:
The number 66 fits into 520 7 times, leaving a remainder of 58.
Put 7 as the next digit of the answer. 
Result so far: 9782.7
Subtract 462 from 520 to get 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Let's proceed to step 8:
If we divide 580 by 66, we get 8 and a remainder of 52.
The number 8 becomes the next digit in our result. 
Result so far: 9782.78
Subtracting 528 from 580 leaves us with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

On to step 9:
66 goes into 520 7 times with a remainder of 58.
Put 7 as the next digit of the answer. 
Result so far: 9782.787
If we take 462 away from 520, we end up with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Going ahead to step 10:
If we divide 580 by 66, we get 8 and a remainder of 52.
The number 8 becomes the next digit in our result. 
Result so far: 9782.7878
If we subtract 528 from 580, we get 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Moving on to step 11:
When dividing 520 by 66, we get 7 with a remainder of 58.
Record the quotient 7 as the next digit in the result. 
Result so far: 9782.78787
Deduct 462 from 520 and we're left with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Going ahead to step 12:
The number 66 fits into 580 8 times, leaving a remainder of 52.
Write down 8 as next digit of the result. 
Result so far: 9782.787878
Subtract 528 from 580 to get 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

On to step 13:
66 can be fit into 520 7 times, resulting in a remainder of 58.
The number 7 becomes the next digit in our result. 
Result so far: 9782.7878787
If we take 462 away from 520, we end up with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Advancing to step 14:
580 divided by 66 is 8 with a remainder of 52.
Record the quotient 8 as the next digit in the result. 
Result so far: 9782.78787878
If we take 528 away from 580, we end up with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

The final result is 9782.78787878 with a remainder of 5.2e-08.