We look at the division of 81660561 by 197 
The aim is to understand the frequency of 197 in 81660561.

Let's proceed to step 1:
The number 197 fits into 8 0 times, leaving a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Fetch the next digit (1) from the dividend, attach it to 8 and continue: 81 / 197

Going ahead to step 2:
The number 197 fits into 81 0 times, leaving a remainder of 81.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 81 leaves us with 81.
Include the next digit (6) from the dividend after 81, then repeat: 816 / 197

Advancing to step 3:
If we divide 816 by 197, we get 4 and a remainder of 28.
Put 4 as the next digit of the answer. 
Result so far: 4.0
The remainder is 28 after subtracting 788 from 816.
Take the next digit (6) from the dividend and append it to 28, then repeat: 286 / 197

Let's proceed to step 4:
197 can be fit into 286 1 times, resulting in a remainder of 89.
Put 1 as the next digit of the answer. 
Result so far: 41.0
If we take 197 away from 286, we end up with 89.
Append the next digit (0) from the dividend to 89 and continue with: 890 / 197

Advancing to step 5:
When dividing 890 by 197, we get 4 with a remainder of 102.
Put 4 as the next digit of the answer. 
Result so far: 414.0
The remainder is 102 after subtracting 788 from 890.
Grab the next digit (5) from the dividend, add it to 102, then carry on: 1025 / 197

Advancing to step 6:
If we divide 1025 by 197, we get 5 and a remainder of 40.
Write down 5 as next digit of the result. 
Result so far: 4145.0
Deduct 985 from 1025 and we're left with 40.
Take the next digit (6) from the dividend and append it to 40, then repeat: 406 / 197

Going ahead to step 7:
When dividing 406 by 197, we get 2 with a remainder of 12.
Write down 2 as next digit of the result. 
Result so far: 41452.0
If we subtract 394 from 406, we get 12.
Include the next digit (1) from the dividend after 12, then repeat: 121 / 197

Moving on to step 8:
121 divided by 197 is 0 with a remainder of 121.
Put 0 as the next digit of the answer. 
Result so far: 414520.0
Subtracting 0 from 121 leaves us with 121.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1210, and continue the process.

Let's proceed to step 9:
197 can be fit into 1210 6 times, resulting in a remainder of 28.
Put 6 as the next digit of the answer. 
Result so far: 414520.6
Deduct 1182 from 1210 and we're left with 28.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

Moving on to step 10:
If we divide 280 by 197, we get 1 and a remainder of 83.
Put 1 as the next digit of the answer. 
Result so far: 414520.61
Deduct 197 from 280 and we're left with 83.
Since there are no more digits in the dividend, we add a zero to the remainder making it 830, and continue the process.

On to step 11:
830 divided by 197 is 4 with a remainder of 42.
The number 4 becomes the next digit in our result. 
Result so far: 414520.614
Subtract 788 from 830 to get 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

Let's proceed to step 12:
420 divided by 197 is 2 with a remainder of 26.
Put 2 as the next digit of the answer. 
Result so far: 414520.6142
If we subtract 394 from 420, we get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

On to step 13:
260 divided by 197 is 1 with a remainder of 63.
Use 1 as the next digit of our solution. 
Result so far: 414520.61421
If we subtract 197 from 260, we get 63.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

Going ahead to step 14:
If we divide 630 by 197, we get 3 and a remainder of 39.
Use 3 as the next digit of our solution. 
Result so far: 414520.614213
The remainder is 39 after subtracting 591 from 630.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Moving on to step 15:
390 divided by 197 is 1 with a remainder of 193.
Write down 1 as next digit of the result. 
Result so far: 414520.6142131
The remainder is 193 after subtracting 197 from 390.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1930, and continue the process.

On to step 16:
197 can be fit into 1930 9 times, resulting in a remainder of 157.
The number 9 becomes the next digit in our result. 
Result so far: 414520.61421319
Subtracting 1773 from 1930 leaves us with 157.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1570, and continue the process.

The final outcome is 414520.61421319, with a leftover of 1.57e-07.