We look at the division of 86399936 by 51 
We want to figure out the number of times 86399936 can be divided by 51.

Step 1:
8 divided by 51 is 0 with a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Bring next digit (6) of the dividend behind the 8 and repeat the process: 86 / 51

Moving on to step 2:
If we divide 86 by 51, we get 1 and a remainder of 35.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
The remainder is 35 after subtracting 51 from 86.
Fetch the next digit (3) from the dividend, attach it to 35 and continue: 353 / 51

Going ahead to step 3:
The number 51 fits into 353 6 times, leaving a remainder of 47.
Use 6 as the next digit of our solution. 
Result so far: 16.0
The remainder is 47 after subtracting 306 from 353.
Include the next digit (9) from the dividend after 47, then repeat: 479 / 51

Moving on to step 4:
The number 51 fits into 479 9 times, leaving a remainder of 20.
The number 9 becomes the next digit in our result. 
Result so far: 169.0
Deduct 459 from 479 and we're left with 20.
Take the next digit (9) from the dividend and append it to 20, then repeat: 209 / 51

Let's proceed to step 5:
51 goes into 209 4 times with a remainder of 5.
Record the quotient 4 as the next digit in the result. 
Result so far: 1694.0
If we subtract 204 from 209, we get 5.
Fetch the next digit (9) from the dividend, attach it to 5 and continue: 59 / 51

Step 6:
59 divided by 51 is 1 with a remainder of 8.
The next digit of our result is 1. 
Result so far: 16941.0
If we subtract 51 from 59, we get 8.
Grab the next digit (3) from the dividend, add it to 8, then carry on: 83 / 51

Moving on to step 7:
The number 51 fits into 83 1 times, leaving a remainder of 32.
The number 1 becomes the next digit in our result. 
Result so far: 169411.0
Deduct 51 from 83 and we're left with 32.
Grab the next digit (6) from the dividend, add it to 32, then carry on: 326 / 51

On to step 8:
326 divided by 51 is 6 with a remainder of 20.
Record the quotient 6 as the next digit in the result. 
Result so far: 1694116.0
Deduct 306 from 326 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 9:
51 goes into 200 3 times with a remainder of 47.
Write down 3 as next digit of the result. 
Result so far: 1694116.3
Subtracting 153 from 200 leaves us with 47.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

Advancing to step 10:
When dividing 470 by 51, we get 9 with a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 1694116.39
If we take 459 away from 470, 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.

Going ahead to step 11:
51 can be fit into 110 2 times, resulting in a remainder of 8.
The next digit of our result is 2. 
Result so far: 1694116.392
The remainder is 8 after subtracting 102 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Going ahead to step 12:
80 divided by 51 is 1 with a remainder of 29.
Write down 1 as next digit of the result. 
Result so far: 1694116.3921
If we take 51 away from 80, we end up with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Let's proceed to step 13:
If we divide 290 by 51, we get 5 and a remainder of 35.
Put 5 as the next digit of the answer. 
Result so far: 1694116.39215
Subtracting 255 from 290 leaves us with 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

Step 14:
51 can be fit into 350 6 times, resulting in a remainder of 44.
Record the quotient 6 as the next digit in the result. 
Result so far: 1694116.392156
If we take 306 away from 350, we end up with 44.
Since there are no more digits in the dividend, we add a zero to the remainder making it 440, and continue the process.

Step 15:
When dividing 440 by 51, we get 8 with a remainder of 32.
Use 8 as the next digit of our solution. 
Result so far: 1694116.3921568
Subtract 408 from 440 to get 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Let's proceed to step 16:
51 can be fit into 320 6 times, resulting in a remainder of 14.
Put 6 as the next digit of the answer. 
Result so far: 1694116.39215686
The remainder is 14 after subtracting 306 from 320.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

After the division, we end up with 1694116.39215686 and a remainder of 1.4e-08.