53863109 ÷ 665 
We want to figure out the number of times 53863109 can be divided by 665.

Advancing to step 1:
The number 665 fits into 5 0 times, leaving a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Bring next digit (3) of the dividend behind the 5 and repeat the process: 53 / 665

Going ahead to step 2:
665 goes into 53 0 times with a remainder of 53.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 53 leaves us with 53.
Include the next digit (8) from the dividend after 53, then repeat: 538 / 665

On to step 3:
If we divide 538 by 665, we get 0 and a remainder of 538.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 538 and we're left with 538.
Fetch the next digit (6) from the dividend, attach it to 538 and continue: 5386 / 665

Going ahead to step 4:
If we divide 5386 by 665, we get 8 and a remainder of 66.
Use 8 as the next digit of our solution. 
Result so far: 8.0
If we subtract 5320 from 5386, we get 66.
Include the next digit (3) from the dividend after 66, then repeat: 663 / 665

Moving on to step 5:
665 goes into 663 0 times with a remainder of 663.
Record the quotient 0 as the next digit in the result. 
Result so far: 80.0
Subtracting 0 from 663 leaves us with 663.
Append the next digit (1) from the dividend to 663 and continue with: 6631 / 665

Moving on to step 6:
665 goes into 6631 9 times with a remainder of 646.
Record the quotient 9 as the next digit in the result. 
Result so far: 809.0
If we subtract 5985 from 6631, we get 646.
Bring next digit (0) of the dividend behind the 646 and repeat the process: 6460 / 665

Moving on to step 7:
665 goes into 6460 9 times with a remainder of 475.
Record the quotient 9 as the next digit in the result. 
Result so far: 8099.0
If we take 5985 away from 6460, we end up with 475.
Take the next digit (9) from the dividend and append it to 475, then repeat: 4759 / 665

Moving on to step 8:
4759 divided by 665 is 7 with a remainder of 104.
Write down 7 as next digit of the result. 
Result so far: 80997.0
Subtract 4655 from 4759 to 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.

Let's proceed to step 9:
1040 divided by 665 is 1 with a remainder of 375.
Put 1 as the next digit of the answer. 
Result so far: 80997.1
Deduct 665 from 1040 and we're left with 375.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3750, and continue the process.

On to step 10:
If we divide 3750 by 665, we get 5 and a remainder of 425.
The number 5 becomes the next digit in our result. 
Result so far: 80997.15
If we subtract 3325 from 3750, we get 425.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4250, and continue the process.

Going ahead to step 11:
665 goes into 4250 6 times with a remainder of 260.
The next digit of our result is 6. 
Result so far: 80997.156
If we take 3990 away from 4250, we end up with 260.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2600, and continue the process.

Step 12:
When dividing 2600 by 665, we get 3 with a remainder of 605.
Put 3 as the next digit of the answer. 
Result so far: 80997.1563
If we take 1995 away from 2600, we end up with 605.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6050, and continue the process.

Moving on to step 13:
The number 665 fits into 6050 9 times, leaving a remainder of 65.
The number 9 becomes the next digit in our result. 
Result so far: 80997.15639
The remainder is 65 after subtracting 5985 from 6050.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Moving on to step 14:
650 divided by 665 is 0 with a remainder of 650.
Write down 0 as next digit of the result. 
Result so far: 80997.15639
Subtract 0 from 650 to get 650.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6500, and continue the process.

Advancing to step 15:
When dividing 6500 by 665, we get 9 with a remainder of 515.
Put 9 as the next digit of the answer. 
Result so far: 80997.1563909
Subtract 5985 from 6500 to get 515.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5150, and continue the process.

Going ahead to step 16:
665 goes into 5150 7 times with a remainder of 495.
Put 7 as the next digit of the answer. 
Result so far: 80997.15639097
Deduct 4655 from 5150 and we're left with 495.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4950, and continue the process.

The quotient of the division is 80997.15639097, and the remainder is 4.95e-07.