We look at the division of 89781065 by 21 
Let's see how many times 21 fits into 89781065.

Step 1:
If we divide 8 by 21, we get 0 and a remainder of 8.
Use 0 as the next digit of our solution. 
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

Step 2:
When dividing 89 by 21, we get 4 with a remainder of 5.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
If we take 84 away from 89, we end up with 5.
Append the next digit (7) from the dividend to 5 and continue with: 57 / 21

Advancing to step 3:
The number 21 fits into 57 2 times, leaving a remainder of 15.
Use 2 as the next digit of our solution. 
Result so far: 42.0
Subtract 42 from 57 to get 15.
Append the next digit (8) from the dividend to 15 and continue with: 158 / 21

On to step 4:
21 goes into 158 7 times with a remainder of 11.
Put 7 as the next digit of the answer. 
Result so far: 427.0
If we subtract 147 from 158, we get 11.
Include the next digit (1) from the dividend after 11, then repeat: 111 / 21

Moving on to step 5:
The number 21 fits into 111 5 times, leaving a remainder of 6.
Use 5 as the next digit of our solution. 
Result so far: 4275.0
Subtracting 105 from 111 leaves us with 6.
Append the next digit (0) from the dividend to 6 and continue with: 60 / 21

Step 6:
21 can be fit into 60 2 times, resulting in a remainder of 18.
Record the quotient 2 as the next digit in the result. 
Result so far: 42752.0
If we take 42 away from 60, we end up with 18.
Take the next digit (6) from the dividend and append it to 18, then repeat: 186 / 21

Step 7:
21 can be fit into 186 8 times, resulting in a remainder of 18.
The next digit of our result is 8. 
Result so far: 427528.0
If we take 168 away from 186, we end up with 18.
Take the next digit (5) from the dividend and append it to 18, then repeat: 185 / 21

Step 8:
The number 21 fits into 185 8 times, leaving a remainder of 17.
The number 8 becomes the next digit in our result. 
Result so far: 4275288.0
Subtracting 168 from 185 leaves us 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.

Step 9:
170 divided by 21 is 8 with a remainder of 2.
The next digit of our result is 8. 
Result so far: 4275288.8
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.

Advancing to step 10:
21 can be fit into 20 0 times, resulting in a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 4275288.8
Subtract 0 from 20 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 11:
The number 21 fits into 200 9 times, leaving a remainder of 11.
The next digit of our result is 9. 
Result so far: 4275288.809
The remainder is 11 after subtracting 189 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Advancing to step 12:
21 can be fit into 110 5 times, resulting in a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 4275288.8095
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.

Advancing to step 13:
When dividing 50 by 21, we get 2 with a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 4275288.80952
Deduct 42 from 50 and we're left 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.

Advancing to step 14:
If we divide 80 by 21, we get 3 and a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 4275288.809523
If we take 63 away from 80, we end up 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.

On to step 15:
170 divided by 21 is 8 with a remainder of 2.
Record the quotient 8 as the next digit in the result. 
Result so far: 4275288.8095238
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.

Step 16:
If we divide 20 by 21, we get 0 and a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 4275288.8095238
Subtracting 0 from 20 leaves us 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.

Our division results in 4275288.8095238 with a remaining 2e-08.