We divide 1571546 by 661
The aim is to understand the frequency of 661 in 1571546.

Step 1:
If we divide 1 by 661, we get 0 and a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Include the next digit (5) from the dividend after 1, then repeat: 15 / 661

On to step 2:
If we divide 15 by 661, we get 0 and a remainder of 15.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 15, we get 15.
Fetch the next digit (7) from the dividend, attach it to 15 and continue: 157 / 661

On to step 3:
661 goes into 157 0 times with a remainder of 157.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 157 leaves us with 157.
Append the next digit (1) from the dividend to 157 and continue with: 1571 / 661

Moving on to step 4:
661 can be fit into 1571 2 times, resulting in a remainder of 249.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
Subtracting 1322 from 1571 leaves us with 249.
Include the next digit (5) from the dividend after 249, then repeat: 2495 / 661

Advancing to step 5:
661 can be fit into 2495 3 times, resulting in a remainder of 512.
Use 3 as the next digit of our solution. 
Result so far: 23.0
Deduct 1983 from 2495 and we're left with 512.
Bring next digit (4) of the dividend behind the 512 and repeat the process: 5124 / 661

Moving on to step 6:
661 goes into 5124 7 times with a remainder of 497.
Record the quotient 7 as the next digit in the result. 
Result so far: 237.0
Subtracting 4627 from 5124 leaves us with 497.
Take the next digit (6) from the dividend and append it to 497, then repeat: 4976 / 661

On to step 7:
4976 divided by 661 is 7 with a remainder of 349.
Use 7 as the next digit of our solution. 
Result so far: 2377.0
Subtract 4627 from 4976 to get 349.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3490, and continue the process.

On to step 8:
The number 661 fits into 3490 5 times, leaving a remainder of 185.
Record the quotient 5 as the next digit in the result. 
Result so far: 2377.5
Deduct 3305 from 3490 and we're left with 185.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1850, and continue the process.

Let's proceed to step 9:
661 can be fit into 1850 2 times, resulting in a remainder of 528.
The number 2 becomes the next digit in our result. 
Result so far: 2377.52
Deduct 1322 from 1850 and we're left with 528.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5280, and continue the process.

On to step 10:
5280 divided by 661 is 7 with a remainder of 653.
The next digit of our result is 7. 
Result so far: 2377.527
Subtract 4627 from 5280 to get 653.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6530, and continue the process.

On to step 11:
661 can be fit into 6530 9 times, resulting in a remainder of 581.
The number 9 becomes the next digit in our result. 
Result so far: 2377.5279
If we subtract 5949 from 6530, we get 581.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5810, and continue the process.

Let's proceed to step 12:
661 can be fit into 5810 8 times, resulting in a remainder of 522.
Put 8 as the next digit of the answer. 
Result so far: 2377.52798
The remainder is 522 after subtracting 5288 from 5810.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5220, and continue the process.

Step 13:
661 can be fit into 5220 7 times, resulting in a remainder of 593.
Use 7 as the next digit of our solution. 
Result so far: 2377.527987
If we take 4627 away from 5220, we end up with 593.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5930, and continue the process.

Moving on to step 14:
661 goes into 5930 8 times with a remainder of 642.
The number 8 becomes the next digit in our result. 
Result so far: 2377.5279878
Subtract 5288 from 5930 to get 642.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6420, and continue the process.

Going ahead to step 15:
When dividing 6420 by 661, we get 9 with a remainder of 471.
Put 9 as the next digit of the answer. 
Result so far: 2377.52798789
Subtract 5949 from 6420 to get 471.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4710, and continue the process.

In conclusion, the division gives 2377.52798789 with a balance of 4.71e-07.