Let's divide 891020 by 21
We want to figure out the number of times 891020 can be divided by 21.

On to step 1:
When dividing 8 by 21, we get 0 with a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Take the next digit (9) from the dividend and append it to 8, then repeat: 89 / 21

On to step 2:
89 divided by 21 is 4 with a remainder of 5.
Write down 4 as next digit of the result. 
Result so far: 4.0
The remainder is 5 after subtracting 84 from 89.
Include the next digit (1) from the dividend after 5, then repeat: 51 / 21

Moving on to step 3:
If we divide 51 by 21, we get 2 and a remainder of 9.
Use 2 as the next digit of our solution. 
Result so far: 42.0
Subtract 42 from 51 to get 9.
Grab the next digit (0) from the dividend, add it to 9, then carry on: 90 / 21

On to step 4:
21 can be fit into 90 4 times, resulting in a remainder of 6.
Write down 4 as next digit of the result. 
Result so far: 424.0
If we subtract 84 from 90, we get 6.
Fetch the next digit (2) from the dividend, attach it to 6 and continue: 62 / 21

Advancing to step 5:
21 can be fit into 62 2 times, resulting in a remainder of 20.
The number 2 becomes the next digit in our result. 
Result so far: 4242.0
The remainder is 20 after subtracting 42 from 62.
Take the next digit (0) from the dividend and append it to 20, then repeat: 200 / 21

On to step 6:
200 divided by 21 is 9 with a remainder of 11.
Put 9 as the next digit of the answer. 
Result so far: 42429.0
Subtracting 189 from 200 leaves us 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.

Moving on to step 7:
110 divided by 21 is 5 with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 42429.5
The remainder is 5 after subtracting 105 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Let's proceed to step 8:
21 goes into 50 2 times with a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 42429.52
Subtract 42 from 50 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 9:
21 can be fit into 80 3 times, resulting in a remainder of 17.
The number 3 becomes the next digit in our result. 
Result so far: 42429.523
If we subtract 63 from 80, 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.

Advancing to step 10:
21 goes into 170 8 times with a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 42429.5238
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.

Advancing to step 11:
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: 42429.5238
The remainder is 20 after subtracting 0 from 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 12:
21 can be fit into 200 9 times, resulting in a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 42429.523809
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.

Step 13:
If we divide 110 by 21, we get 5 and a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 42429.5238095
If we take 105 away from 110, we end up with 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 14:
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: 42429.52380952
Subtract 42 from 50 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

The quotient of the division is 42429.52380952, and the remainder is 8e-09.