898835 ÷ 21 
The aim is to understand the frequency of 21 in 898835.

On to step 1:
21 can be fit into 8 0 times, resulting in a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Fetch the next digit (9) from the dividend, attach it to 8 and continue: 89 / 21

Moving on to step 2:
If we divide 89 by 21, we get 4 and a remainder of 5.
Write down 4 as next digit of the result. 
Result so far: 4.0
Subtract 84 from 89 to get 5.
Grab the next digit (8) from the dividend, add it to 5, then carry on: 58 / 21

Going ahead to step 3:
58 divided by 21 is 2 with a remainder of 16.
Record the quotient 2 as the next digit in the result. 
Result so far: 42.0
If we subtract 42 from 58, we get 16.
Fetch the next digit (8) from the dividend, attach it to 16 and continue: 168 / 21

Moving on to step 4:
If we divide 168 by 21, we get 8 and a remainder of 0.
The next digit of our result is 8. 
Result so far: 428.0
The remainder is 0 after subtracting 168 from 168.
Grab the next digit (3) from the dividend, add it to 0, then carry on: 3 / 21

Let's proceed to step 5:
The number 21 fits into 3 0 times, leaving a remainder of 3.
Record the quotient 0 as the next digit in the result. 
Result so far: 4280.0
The remainder is 3 after subtracting 0 from 3.
Append the next digit (5) from the dividend to 3 and continue with: 35 / 21

Step 6:
21 goes into 35 1 times with a remainder of 14.
The number 1 becomes the next digit in our result. 
Result so far: 42801.0
If we take 21 away from 35, we end up with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Step 7:
140 divided by 21 is 6 with a remainder of 14.
Write down 6 as next digit of the result. 
Result so far: 42801.6
The remainder is 14 after subtracting 126 from 140.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Let's proceed to step 8:
If we divide 140 by 21, we get 6 and a remainder of 14.
The number 6 becomes the next digit in our result. 
Result so far: 42801.66
Subtracting 126 from 140 leaves us with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

The final outcome is 42801.66, with a leftover of 0.014.