66712491 ÷ 257 
We want to figure out the number of times 66712491 can be divided by 257.

Advancing to step 1:
257 goes into 6 0 times with a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Include the next digit (6) from the dividend after 6, then repeat: 66 / 257

Advancing to step 2:
66 divided by 257 is 0 with a remainder of 66.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 66 leaves us with 66.
Append the next digit (7) from the dividend to 66 and continue with: 667 / 257

Step 3:
The number 257 fits into 667 2 times, leaving a remainder of 153.
Put 2 as the next digit of the answer. 
Result so far: 2.0
The remainder is 153 after subtracting 514 from 667.
Bring next digit (1) of the dividend behind the 153 and repeat the process: 1531 / 257

On to step 4:
257 can be fit into 1531 5 times, resulting in a remainder of 246.
Put 5 as the next digit of the answer. 
Result so far: 25.0
Subtracting 1285 from 1531 leaves us with 246.
Take the next digit (2) from the dividend and append it to 246, then repeat: 2462 / 257

Let's proceed to step 5:
If we divide 2462 by 257, we get 9 and a remainder of 149.
Put 9 as the next digit of the answer. 
Result so far: 259.0
Subtracting 2313 from 2462 leaves us with 149.
Grab the next digit (4) from the dividend, add it to 149, then carry on: 1494 / 257

Advancing to step 6:
257 can be fit into 1494 5 times, resulting in a remainder of 209.
Put 5 as the next digit of the answer. 
Result so far: 2595.0
Deduct 1285 from 1494 and we're left with 209.
Take the next digit (9) from the dividend and append it to 209, then repeat: 2099 / 257

Advancing to step 7:
2099 divided by 257 is 8 with a remainder of 43.
Record the quotient 8 as the next digit in the result. 
Result so far: 25958.0
Subtract 2056 from 2099 to get 43.
Append the next digit (1) from the dividend to 43 and continue with: 431 / 257

Going ahead to step 8:
431 divided by 257 is 1 with a remainder of 174.
Write down 1 as next digit of the result. 
Result so far: 259581.0
If we take 257 away from 431, we end up with 174.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1740, and continue the process.

On to step 9:
1740 divided by 257 is 6 with a remainder of 198.
Record the quotient 6 as the next digit in the result. 
Result so far: 259581.6
Deduct 1542 from 1740 and we're left with 198.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1980, and continue the process.

Let's proceed to step 10:
257 goes into 1980 7 times with a remainder of 181.
Use 7 as the next digit of our solution. 
Result so far: 259581.67
If we take 1799 away from 1980, we end up with 181.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1810, and continue the process.

Moving on to step 11:
1810 divided by 257 is 7 with a remainder of 11.
Put 7 as the next digit of the answer. 
Result so far: 259581.677
If we take 1799 away from 1810, we end up with 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 outcome is 259581.677, with a leftover of 0.0011.