We divide 83856562 by 21
The aim is to understand the frequency of 21 in 83856562.

On to step 1:
8 divided by 21 is 0 with a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Include the next digit (3) from the dividend after 8, then repeat: 83 / 21

On to step 2:
83 divided by 21 is 3 with a remainder of 20.
Put 3 as the next digit of the answer. 
Result so far: 3.0
Deduct 63 from 83 and we're left with 20.
Include the next digit (8) from the dividend after 20, then repeat: 208 / 21

Step 3:
21 can be fit into 208 9 times, resulting in a remainder of 19.
Record the quotient 9 as the next digit in the result. 
Result so far: 39.0
Deduct 189 from 208 and we're left with 19.
Bring next digit (5) of the dividend behind the 19 and repeat the process: 195 / 21

Going ahead to step 4:
The number 21 fits into 195 9 times, leaving a remainder of 6.
Write down 9 as next digit of the result. 
Result so far: 399.0
If we take 189 away from 195, we end up with 6.
Include the next digit (6) from the dividend after 6, then repeat: 66 / 21

On to step 5:
21 goes into 66 3 times with a remainder of 3.
Use 3 as the next digit of our solution. 
Result so far: 3993.0
Subtracting 63 from 66 leaves us with 3.
Append the next digit (5) from the dividend to 3 and continue with: 35 / 21

Going ahead to step 6:
21 can be fit into 35 1 times, resulting in a remainder of 14.
Record the quotient 1 as the next digit in the result. 
Result so far: 39931.0
If we subtract 21 from 35, we get 14.
Fetch the next digit (6) from the dividend, attach it to 14 and continue: 146 / 21

Step 7:
21 can be fit into 146 6 times, resulting in a remainder of 20.
Record the quotient 6 as the next digit in the result. 
Result so far: 399316.0
Subtracting 126 from 146 leaves us with 20.
Grab the next digit (2) from the dividend, add it to 20, then carry on: 202 / 21

On to step 8:
When dividing 202 by 21, we get 9 with a remainder of 13.
Use 9 as the next digit of our solution. 
Result so far: 3993169.0
Deduct 189 from 202 and we're left with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Moving on to step 9:
When dividing 130 by 21, we get 6 with a remainder of 4.
Use 6 as the next digit of our solution. 
Result so far: 3993169.6
Subtract 126 from 130 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 10:
21 can be fit into 40 1 times, resulting in a remainder of 19.
Put 1 as the next digit of the answer. 
Result so far: 3993169.61
Subtracting 21 from 40 leaves us with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Going ahead to step 11:
The number 21 fits into 190 9 times, leaving a remainder of 1.
Write down 9 as next digit of the result. 
Result so far: 3993169.619
The remainder is 1 after subtracting 189 from 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 12:
10 divided by 21 is 0 with a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 3993169.619
Deduct 0 from 10 and we're left with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 13:
The number 21 fits into 100 4 times, leaving a remainder of 16.
The next digit of our result is 4. 
Result so far: 3993169.61904
The remainder is 16 after subtracting 84 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Advancing to step 14:
The number 21 fits into 160 7 times, leaving a remainder of 13.
Use 7 as the next digit of our solution. 
Result so far: 3993169.619047
Subtract 147 from 160 to get 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

On to step 15:
When dividing 130 by 21, we get 6 with a remainder of 4.
Write down 6 as next digit of the result. 
Result so far: 3993169.6190476
Subtracting 126 from 130 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Going ahead to step 16:
40 divided by 21 is 1 with a remainder of 19.
The next digit of our result is 1. 
Result so far: 3993169.61904761
If we take 21 away from 40, we end up with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

In conclusion, the division gives 3993169.61904761 with a balance of 1.9e-08.