66503721 ÷ 521 
Let's see how many times 521 fits into 66503721.

Step 1:
521 can be fit into 6 0 times, resulting in a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Bring next digit (6) of the dividend behind the 6 and repeat the process: 66 / 521

Let's proceed to step 2:
If we divide 66 by 521, we get 0 and a remainder of 66.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 66 leaves us with 66.
Fetch the next digit (5) from the dividend, attach it to 66 and continue: 665 / 521

Let's proceed to step 3:
521 goes into 665 1 times with a remainder of 144.
Write down 1 as next digit of the result. 
Result so far: 1.0
The remainder is 144 after subtracting 521 from 665.
Grab the next digit (0) from the dividend, add it to 144, then carry on: 1440 / 521

Let's proceed to step 4:
1440 divided by 521 is 2 with a remainder of 398.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
Deduct 1042 from 1440 and we're left with 398.
Bring next digit (3) of the dividend behind the 398 and repeat the process: 3983 / 521

Moving on to step 5:
When dividing 3983 by 521, we get 7 with a remainder of 336.
Put 7 as the next digit of the answer. 
Result so far: 127.0
The remainder is 336 after subtracting 3647 from 3983.
Take the next digit (7) from the dividend and append it to 336, then repeat: 3367 / 521

Going ahead to step 6:
521 goes into 3367 6 times with a remainder of 241.
Put 6 as the next digit of the answer. 
Result so far: 1276.0
Subtract 3126 from 3367 to get 241.
Fetch the next digit (2) from the dividend, attach it to 241 and continue: 2412 / 521

Going ahead to step 7:
When dividing 2412 by 521, we get 4 with a remainder of 328.
Use 4 as the next digit of our solution. 
Result so far: 12764.0
If we take 2084 away from 2412, we end up with 328.
Fetch the next digit (1) from the dividend, attach it to 328 and continue: 3281 / 521

Let's proceed to step 8:
When dividing 3281 by 521, we get 6 with a remainder of 155.
Use 6 as the next digit of our solution. 
Result so far: 127646.0
Subtract 3126 from 3281 to get 155.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1550, and continue the process.

On to step 9:
521 goes into 1550 2 times with a remainder of 508.
Write down 2 as next digit of the result. 
Result so far: 127646.2
Deduct 1042 from 1550 and we're left with 508.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5080, and continue the process.

Moving on to step 10:
If we divide 5080 by 521, we get 9 and a remainder of 391.
Record the quotient 9 as the next digit in the result. 
Result so far: 127646.29
Deduct 4689 from 5080 and we're left with 391.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3910, and continue the process.

Let's proceed to step 11:
521 can be fit into 3910 7 times, resulting in a remainder of 263.
Put 7 as the next digit of the answer. 
Result so far: 127646.297
Deduct 3647 from 3910 and we're left with 263.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2630, and continue the process.

Advancing to step 12:
521 goes into 2630 5 times with a remainder of 25.
Record the quotient 5 as the next digit in the result. 
Result so far: 127646.2975
If we take 2605 away from 2630, we end up with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Advancing to step 13:
250 divided by 521 is 0 with a remainder of 250.
Write down 0 as next digit of the result. 
Result so far: 127646.2975
Subtracting 0 from 250 leaves us with 250.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2500, and continue the process.

Going ahead to step 14:
521 goes into 2500 4 times with a remainder of 416.
Use 4 as the next digit of our solution. 
Result so far: 127646.297504
If we subtract 2084 from 2500, we get 416.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4160, and continue the process.

Step 15:
4160 divided by 521 is 7 with a remainder of 513.
The number 7 becomes the next digit in our result. 
Result so far: 127646.2975047
The remainder is 513 after subtracting 3647 from 4160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5130, and continue the process.

Going ahead to step 16:
5130 divided by 521 is 9 with a remainder of 441.
The next digit of our result is 9. 
Result so far: 127646.29750479
Subtracting 4689 from 5130 leaves us with 441.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4410, and continue the process.

The final result is 127646.29750479 with a remainder of 4.41e-07.