21441509 ÷ 861 
The aim is to understand the frequency of 861 in 21441509.

Moving on to step 1:
2 divided by 861 is 0 with a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 861

Step 2:
861 can be fit into 21 0 times, resulting in a remainder of 21.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 21 after subtracting 0 from 21.
Fetch the next digit (4) from the dividend, attach it to 21 and continue: 214 / 861

Let's proceed to step 3:
214 divided by 861 is 0 with a remainder of 214.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 214 and we're left with 214.
Take the next digit (4) from the dividend and append it to 214, then repeat: 2144 / 861

On to step 4:
861 can be fit into 2144 2 times, resulting in a remainder of 422.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
If we subtract 1722 from 2144, we get 422.
Include the next digit (1) from the dividend after 422, then repeat: 4221 / 861

Going ahead to step 5:
861 goes into 4221 4 times with a remainder of 777.
Put 4 as the next digit of the answer. 
Result so far: 24.0
Subtracting 3444 from 4221 leaves us with 777.
Append the next digit (5) from the dividend to 777 and continue with: 7775 / 861

On to step 6:
When dividing 7775 by 861, we get 9 with a remainder of 26.
Use 9 as the next digit of our solution. 
Result so far: 249.0
Subtract 7749 from 7775 to get 26.
Bring next digit (0) of the dividend behind the 26 and repeat the process: 260 / 861

On to step 7:
When dividing 260 by 861, we get 0 with a remainder of 260.
The next digit of our result is 0. 
Result so far: 2490.0
If we subtract 0 from 260, we get 260.
Take the next digit (9) from the dividend and append it to 260, then repeat: 2609 / 861

Let's proceed to step 8:
The number 861 fits into 2609 3 times, leaving a remainder of 26.
The number 3 becomes the next digit in our result. 
Result so far: 24903.0
If we subtract 2583 from 2609, 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.

Step 9:
If we divide 260 by 861, we get 0 and a remainder of 260.
Write down 0 as next digit of the result. 
Result so far: 24903.0
Deduct 0 from 260 and we're left with 260.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2600, and continue the process.

Advancing to step 10:
When dividing 2600 by 861, we get 3 with a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 24903.03
If we subtract 2583 from 2600, we get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Step 11:
170 divided by 861 is 0 with a remainder of 170.
The number 0 becomes the next digit in our result. 
Result so far: 24903.03
The remainder is 170 after subtracting 0 from 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1700, and continue the process.

On to step 12:
861 can be fit into 1700 1 times, resulting in a remainder of 839.
Record the quotient 1 as the next digit in the result. 
Result so far: 24903.0301
The remainder is 839 after subtracting 861 from 1700.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8390, and continue the process.

Advancing to step 13:
If we divide 8390 by 861, we get 9 and a remainder of 641.
The number 9 becomes the next digit in our result. 
Result so far: 24903.03019
If we subtract 7749 from 8390, we get 641.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6410, and continue the process.

Moving on to step 14:
If we divide 6410 by 861, we get 7 and a remainder of 383.
Put 7 as the next digit of the answer. 
Result so far: 24903.030197
If we subtract 6027 from 6410, we get 383.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3830, and continue the process.

Going ahead to step 15:
The number 861 fits into 3830 4 times, leaving a remainder of 386.
Record the quotient 4 as the next digit in the result. 
Result so far: 24903.0301974
Subtracting 3444 from 3830 leaves us with 386.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3860, and continue the process.

Advancing to step 16:
When dividing 3860 by 861, we get 4 with a remainder of 416.
Write down 4 as next digit of the result. 
Result so far: 24903.03019744
If we subtract 3444 from 3860, we get 416.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4160, and continue the process.

The final outcome is 24903.03019744, with a leftover of 4.16e-07.