We look at the division of 20581997 by 811 
The aim is to understand the frequency of 811 in 20581997.

On to step 1:
If we divide 2 by 811, we get 0 and a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 2 leaves us with 2.
Take the next digit (0) from the dividend and append it to 2, then repeat: 20 / 811

Moving on to step 2:
If we divide 20 by 811, we get 0 and a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 20, we end up with 20.
Bring next digit (5) of the dividend behind the 20 and repeat the process: 205 / 811

Advancing to step 3:
The number 811 fits into 205 0 times, leaving a remainder of 205.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 205 after subtracting 0 from 205.
Fetch the next digit (8) from the dividend, attach it to 205 and continue: 2058 / 811

Moving on to step 4:
811 goes into 2058 2 times with a remainder of 436.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
Subtracting 1622 from 2058 leaves us with 436.
Append the next digit (1) from the dividend to 436 and continue with: 4361 / 811

Step 5:
The number 811 fits into 4361 5 times, leaving a remainder of 306.
Record the quotient 5 as the next digit in the result. 
Result so far: 25.0
If we subtract 4055 from 4361, we get 306.
Fetch the next digit (9) from the dividend, attach it to 306 and continue: 3069 / 811

Advancing to step 6:
811 can be fit into 3069 3 times, resulting in a remainder of 636.
Write down 3 as next digit of the result. 
Result so far: 253.0
The remainder is 636 after subtracting 2433 from 3069.
Fetch the next digit (9) from the dividend, attach it to 636 and continue: 6369 / 811

Step 7:
6369 divided by 811 is 7 with a remainder of 692.
The next digit of our result is 7. 
Result so far: 2537.0
If we subtract 5677 from 6369, we get 692.
Fetch the next digit (7) from the dividend, attach it to 692 and continue: 6927 / 811

Advancing to step 8:
811 goes into 6927 8 times with a remainder of 439.
Use 8 as the next digit of our solution. 
Result so far: 25378.0
Subtracting 6488 from 6927 leaves us with 439.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4390, and continue the process.

On to step 9:
The number 811 fits into 4390 5 times, leaving a remainder of 335.
The number 5 becomes the next digit in our result. 
Result so far: 25378.5
Deduct 4055 from 4390 and we're left with 335.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3350, and continue the process.

On to step 10:
The number 811 fits into 3350 4 times, leaving a remainder of 106.
The number 4 becomes the next digit in our result. 
Result so far: 25378.54
The remainder is 106 after subtracting 3244 from 3350.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1060, and continue the process.

Moving on to step 11:
When dividing 1060 by 811, we get 1 with a remainder of 249.
Write down 1 as next digit of the result. 
Result so far: 25378.541
Deduct 811 from 1060 and we're left with 249.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2490, and continue the process.

Let's proceed to step 12:
When dividing 2490 by 811, we get 3 with a remainder of 57.
Record the quotient 3 as the next digit in the result. 
Result so far: 25378.5413
If we subtract 2433 from 2490, we get 57.
Since there are no more digits in the dividend, we add a zero to the remainder making it 570, and continue the process.

Advancing to step 13:
If we divide 570 by 811, we get 0 and a remainder of 570.
Write down 0 as next digit of the result. 
Result so far: 25378.5413
The remainder is 570 after subtracting 0 from 570.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5700, and continue the process.

Let's proceed to step 14:
811 can be fit into 5700 7 times, resulting in a remainder of 23.
Put 7 as the next digit of the answer. 
Result so far: 25378.541307
If we take 5677 away from 5700, we end up with 23.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

Advancing to step 15:
811 can be fit into 230 0 times, resulting in a remainder of 230.
Use 0 as the next digit of our solution. 
Result so far: 25378.541307
Deduct 0 from 230 and we're left with 230.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2300, and continue the process.

Advancing to step 16:
811 goes into 2300 2 times with a remainder of 678.
Put 2 as the next digit of the answer. 
Result so far: 25378.54130702
If we subtract 1622 from 2300, we get 678.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6780, and continue the process.

The final result is 25378.54130702 with a remainder of 6.78e-07.