51371527 ÷ 397 
The aim is to understand the frequency of 397 in 51371527.

Moving on to step 1:
When dividing 5 by 397, we get 0 with a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 5, we end up with 5.
Grab the next digit (1) from the dividend, add it to 5, then carry on: 51 / 397

Going ahead to step 2:
397 goes into 51 0 times with a remainder of 51.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 51 and we're left with 51.
Take the next digit (3) from the dividend and append it to 51, then repeat: 513 / 397

Let's proceed to step 3:
397 can be fit into 513 1 times, resulting in a remainder of 116.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we subtract 397 from 513, we get 116.
Fetch the next digit (7) from the dividend, attach it to 116 and continue: 1167 / 397

On to step 4:
The number 397 fits into 1167 2 times, leaving a remainder of 373.
The next digit of our result is 2. 
Result so far: 12.0
Deduct 794 from 1167 and we're left with 373.
Bring next digit (1) of the dividend behind the 373 and repeat the process: 3731 / 397

On to step 5:
3731 divided by 397 is 9 with a remainder of 158.
Use 9 as the next digit of our solution. 
Result so far: 129.0
The remainder is 158 after subtracting 3573 from 3731.
Take the next digit (5) from the dividend and append it to 158, then repeat: 1585 / 397

Step 6:
397 can be fit into 1585 3 times, resulting in a remainder of 394.
Write down 3 as next digit of the result. 
Result so far: 1293.0
If we subtract 1191 from 1585, we get 394.
Fetch the next digit (2) from the dividend, attach it to 394 and continue: 3942 / 397

Moving on to step 7:
The number 397 fits into 3942 9 times, leaving a remainder of 369.
Record the quotient 9 as the next digit in the result. 
Result so far: 12939.0
Subtract 3573 from 3942 to get 369.
Fetch the next digit (7) from the dividend, attach it to 369 and continue: 3697 / 397

Advancing to step 8:
397 goes into 3697 9 times with a remainder of 124.
Put 9 as the next digit of the answer. 
Result so far: 129399.0
Subtracting 3573 from 3697 leaves us 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.

Let's proceed to step 9:
The number 397 fits into 1240 3 times, leaving a remainder of 49.
Write down 3 as next digit of the result. 
Result so far: 129399.3
Subtracting 1191 from 1240 leaves us with 49.
Since there are no more digits in the dividend, we add a zero to the remainder making it 490, and continue the process.

Going ahead to step 10:
If we divide 490 by 397, we get 1 and a remainder of 93.
The number 1 becomes the next digit in our result. 
Result so far: 129399.31
The remainder is 93 after subtracting 397 from 490.
Since there are no more digits in the dividend, we add a zero to the remainder making it 930, and continue the process.

Advancing to step 11:
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: 129399.312
If we take 794 away from 930, we end up with 136.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1360, and continue the process.

Step 12:
If we divide 1360 by 397, we get 3 and a remainder of 169.
Put 3 as the next digit of the answer. 
Result so far: 129399.3123
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.

Moving on to step 13:
397 can be fit into 1690 4 times, resulting in a remainder of 102.
Write down 4 as next digit of the result. 
Result so far: 129399.31234
Subtracting 1588 from 1690 leaves us with 102.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1020, and continue the process.

Advancing to step 14:
When dividing 1020 by 397, we get 2 with a remainder of 226.
The next digit of our result is 2. 
Result so far: 129399.312342
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.

Step 15:
2260 divided by 397 is 5 with a remainder of 275.
The next digit of our result is 5. 
Result so far: 129399.3123425
If we take 1985 away from 2260, we end up with 275.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2750, and continue the process.

Step 16:
2750 divided by 397 is 6 with a remainder of 368.
The number 6 becomes the next digit in our result. 
Result so far: 129399.31234256
Subtracting 2382 from 2750 leaves us with 368.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3680, and continue the process.

The final outcome is 129399.31234256, with a leftover of 3.68e-07.