676160 ÷ 21 
The aim is to understand the frequency of 21 in 676160.

Going ahead to step 1:
When dividing 6 by 21, we get 0 with a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Take the next digit (7) from the dividend and append it to 6, then repeat: 67 / 21

Advancing to step 2:
21 goes into 67 3 times with a remainder of 4.
The next digit of our result is 3. 
Result so far: 3.0
If we subtract 63 from 67, we get 4.
Grab the next digit (6) from the dividend, add it to 4, then carry on: 46 / 21

Going ahead to step 3:
If we divide 46 by 21, we get 2 and a remainder of 4.
Record the quotient 2 as the next digit in the result. 
Result so far: 32.0
Deduct 42 from 46 and we're left with 4.
Bring next digit (1) of the dividend behind the 4 and repeat the process: 41 / 21

On to step 4:
41 divided by 21 is 1 with a remainder of 20.
Write down 1 as next digit of the result. 
Result so far: 321.0
If we subtract 21 from 41, we get 20.
Append the next digit (6) from the dividend to 20 and continue with: 206 / 21

On to step 5:
The number 21 fits into 206 9 times, leaving a remainder of 17.
The next digit of our result is 9. 
Result so far: 3219.0
Subtract 189 from 206 to get 17.
Take the next digit (0) from the dividend and append it to 17, then repeat: 170 / 21

Going ahead to step 6:
When dividing 170 by 21, we get 8 with a remainder of 2.
Write down 8 as next digit of the result. 
Result so far: 32198.0
Subtracting 168 from 170 leaves us with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Let's proceed to step 7:
If we divide 20 by 21, we get 0 and a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 32198.0
If we take 0 away from 20, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Let's proceed to step 8:
The number 21 fits into 200 9 times, leaving a remainder of 11.
Write down 9 as next digit of the result. 
Result so far: 32198.09
Subtract 189 from 200 to get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Moving on to step 9:
21 goes into 110 5 times with a remainder of 5.
The next digit of our result is 5. 
Result so far: 32198.095
If we subtract 105 from 110, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Advancing to step 10:
If we divide 50 by 21, we get 2 and a remainder of 8.
The next digit of our result is 2. 
Result so far: 32198.0952
If we take 42 away from 50, we end up with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 11:
When dividing 80 by 21, we get 3 with a remainder of 17.
Put 3 as the next digit of the answer. 
Result so far: 32198.09523
Deduct 63 from 80 and we're left with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Moving on to step 12:
When dividing 170 by 21, we get 8 with a remainder of 2.
Record the quotient 8 as the next digit in the result. 
Result so far: 32198.095238
The remainder is 2 after subtracting 168 from 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 13:
21 can be fit into 20 0 times, resulting in a remainder of 20.
Put 0 as the next digit of the answer. 
Result so far: 32198.095238
Deduct 0 from 20 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Step 14:
21 goes into 200 9 times with a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 32198.09523809
Deduct 189 from 200 and we're left with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Our division results in 32198.09523809 with a remaining 1.1e-08.