We look at the division of 51231592 by 397 
We want to figure out the number of times 51231592 can be divided by 397.

On to step 1:
5 divided by 397 is 0 with a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 5, we get 5.
Take the next digit (1) from the dividend and append it to 5, then repeat: 51 / 397

Going ahead to step 2:
397 goes into 51 0 times with a remainder of 51.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 51 after subtracting 0 from 51.
Bring next digit (2) of the dividend behind the 51 and repeat the process: 512 / 397

Going ahead to step 3:
When dividing 512 by 397, we get 1 with a remainder of 115.
The next digit of our result is 1. 
Result so far: 1.0
Deduct 397 from 512 and we're left with 115.
Fetch the next digit (3) from the dividend, attach it to 115 and continue: 1153 / 397

Step 4:
When dividing 1153 by 397, we get 2 with a remainder of 359.
Record the quotient 2 as the next digit in the result. 
Result so far: 12.0
If we subtract 794 from 1153, we get 359.
Take the next digit (1) from the dividend and append it to 359, then repeat: 3591 / 397

On to step 5:
397 goes into 3591 9 times with a remainder of 18.
Put 9 as the next digit of the answer. 
Result so far: 129.0
Subtracting 3573 from 3591 leaves us with 18.
Grab the next digit (5) from the dividend, add it to 18, then carry on: 185 / 397

Moving on to step 6:
185 divided by 397 is 0 with a remainder of 185.
The next digit of our result is 0. 
Result so far: 1290.0
If we subtract 0 from 185, we get 185.
Take the next digit (9) from the dividend and append it to 185, then repeat: 1859 / 397

On to step 7:
397 can be fit into 1859 4 times, resulting in a remainder of 271.
Write down 4 as next digit of the result. 
Result so far: 12904.0
Deduct 1588 from 1859 and we're left with 271.
Append the next digit (2) from the dividend to 271 and continue with: 2712 / 397

Moving on to step 8:
2712 divided by 397 is 6 with a remainder of 330.
Write down 6 as next digit of the result. 
Result so far: 129046.0
Deduct 2382 from 2712 and we're left with 330.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3300, and continue the process.

On to step 9:
397 goes into 3300 8 times with a remainder of 124.
Use 8 as the next digit of our solution. 
Result so far: 129046.8
If we take 3176 away from 3300, we end up with 124.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1240, and continue the process.

Step 10:
When dividing 1240 by 397, we get 3 with a remainder of 49.
Write down 3 as next digit of the result. 
Result so far: 129046.83
If we subtract 1191 from 1240, we get 49.
Since there are no more digits in the dividend, we add a zero to the remainder making it 490, and continue the process.

Advancing to step 11:
The number 397 fits into 490 1 times, leaving a remainder of 93.
Put 1 as the next digit of the answer. 
Result so far: 129046.831
Subtract 397 from 490 to get 93.
Since there are no more digits in the dividend, we add a zero to the remainder making it 930, and continue the process.

Step 12:
The number 397 fits into 930 2 times, leaving a remainder of 136.
Use 2 as the next digit of our solution. 
Result so far: 129046.8312
Subtract 794 from 930 to get 136.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1360, and continue the process.

Going ahead to step 13:
397 goes into 1360 3 times with a remainder of 169.
The next digit of our result is 3. 
Result so far: 129046.83123
If we take 1191 away from 1360, we end up with 169.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1690, and continue the process.

Let's proceed to step 14:
397 goes into 1690 4 times with a remainder of 102.
Put 4 as the next digit of the answer. 
Result so far: 129046.831234
The remainder is 102 after subtracting 1588 from 1690.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1020, and continue the process.

Moving on to step 15:
1020 divided by 397 is 2 with a remainder of 226.
The next digit of our result is 2. 
Result so far: 129046.8312342
Subtracting 794 from 1020 leaves us with 226.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2260, and continue the process.

Let's proceed to step 16:
When dividing 2260 by 397, we get 5 with a remainder of 275.
The number 5 becomes the next digit in our result. 
Result so far: 129046.83123425
Subtract 1985 from 2260 to get 275.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2750, and continue the process.

The final outcome is 129046.83123425, with a leftover of 2.75e-07.