We're dividing 12391961 by 618 
Let's see how many times 618 fits into 12391961.

Going ahead to step 1:
618 can be fit into 1 0 times, resulting in a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 618

Let's proceed to step 2:
The number 618 fits into 12 0 times, leaving a remainder of 12.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 12, we get 12.
Grab the next digit (3) from the dividend, add it to 12, then carry on: 123 / 618

Advancing to step 3:
When dividing 123 by 618, we get 0 with a remainder of 123.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 123 to get 123.
Append the next digit (9) from the dividend to 123 and continue with: 1239 / 618

On to step 4:
The number 618 fits into 1239 2 times, leaving a remainder of 3.
Use 2 as the next digit of our solution. 
Result so far: 2.0
The remainder is 3 after subtracting 1236 from 1239.
Bring next digit (1) of the dividend behind the 3 and repeat the process: 31 / 618

Going ahead to step 5:
618 goes into 31 0 times with a remainder of 31.
Write down 0 as next digit of the result. 
Result so far: 20.0
Subtract 0 from 31 to get 31.
Fetch the next digit (9) from the dividend, attach it to 31 and continue: 319 / 618

Advancing to step 6:
The number 618 fits into 319 0 times, leaving a remainder of 319.
Put 0 as the next digit of the answer. 
Result so far: 200.0
Subtracting 0 from 319 leaves us with 319.
Grab the next digit (6) from the dividend, add it to 319, then carry on: 3196 / 618

Moving on to step 7:
When dividing 3196 by 618, we get 5 with a remainder of 106.
The number 5 becomes the next digit in our result. 
Result so far: 2005.0
If we take 3090 away from 3196, we end up with 106.
Bring next digit (1) of the dividend behind the 106 and repeat the process: 1061 / 618

Advancing to step 8:
618 goes into 1061 1 times with a remainder of 443.
The number 1 becomes the next digit in our result. 
Result so far: 20051.0
Subtracting 618 from 1061 leaves us with 443.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4430, and continue the process.

Moving on to step 9:
618 goes into 4430 7 times with a remainder of 104.
Record the quotient 7 as the next digit in the result. 
Result so far: 20051.7
If we subtract 4326 from 4430, we get 104.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1040, and continue the process.

Moving on to step 10:
If we divide 1040 by 618, we get 1 and a remainder of 422.
Put 1 as the next digit of the answer. 
Result so far: 20051.71
The remainder is 422 after subtracting 618 from 1040.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4220, and continue the process.

Let's proceed to step 11:
618 goes into 4220 6 times with a remainder of 512.
The next digit of our result is 6. 
Result so far: 20051.716
If we subtract 3708 from 4220, we get 512.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5120, and continue the process.

Going ahead to step 12:
If we divide 5120 by 618, we get 8 and a remainder of 176.
Use 8 as the next digit of our solution. 
Result so far: 20051.7168
If we take 4944 away from 5120, we end up with 176.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1760, and continue the process.

On to step 13:
The number 618 fits into 1760 2 times, leaving a remainder of 524.
Put 2 as the next digit of the answer. 
Result so far: 20051.71682
Subtract 1236 from 1760 to get 524.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5240, and continue the process.

Going ahead to step 14:
When dividing 5240 by 618, we get 8 with a remainder of 296.
The number 8 becomes the next digit in our result. 
Result so far: 20051.716828
Subtract 4944 from 5240 to get 296.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2960, and continue the process.

Let's proceed to step 15:
The number 618 fits into 2960 4 times, leaving a remainder of 488.
Write down 4 as next digit of the result. 
Result so far: 20051.7168284
Deduct 2472 from 2960 and we're left with 488.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4880, and continue the process.

Step 16:
When dividing 4880 by 618, we get 7 with a remainder of 554.
Put 7 as the next digit of the answer. 
Result so far: 20051.71682847
The remainder is 554 after subtracting 4326 from 4880.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5540, and continue the process.

The final outcome is 20051.71682847, with a leftover of 5.54e-07.