We look at the division of 20011897 by 21 
We're looking to find how many times 21 goes into 20011897.

Advancing to step 1:
21 can be fit into 2 0 times, resulting in a remainder of 2.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Fetch the next digit (0) from the dividend, attach it to 2 and continue: 20 / 21

Step 2:
20 divided by 21 is 0 with a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 20 leaves us with 20.
Bring next digit (0) of the dividend behind the 20 and repeat the process: 200 / 21

On to step 3:
The number 21 fits into 200 9 times, leaving a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 9.0
Subtracting 189 from 200 leaves us with 11.
Include the next digit (1) from the dividend after 11, then repeat: 111 / 21

Moving on to step 4:
21 goes into 111 5 times with a remainder of 6.
Use 5 as the next digit of our solution. 
Result so far: 95.0
Subtracting 105 from 111 leaves us with 6.
Take the next digit (1) from the dividend and append it to 6, then repeat: 61 / 21

Let's proceed to step 5:
The number 21 fits into 61 2 times, leaving a remainder of 19.
Record the quotient 2 as the next digit in the result. 
Result so far: 952.0
Subtracting 42 from 61 leaves us with 19.
Bring next digit (8) of the dividend behind the 19 and repeat the process: 198 / 21

Step 6:
21 can be fit into 198 9 times, resulting in a remainder of 9.
The number 9 becomes the next digit in our result. 
Result so far: 9529.0
If we subtract 189 from 198, we get 9.
Include the next digit (9) from the dividend after 9, then repeat: 99 / 21

Let's proceed to step 7:
99 divided by 21 is 4 with a remainder of 15.
Write down 4 as next digit of the result. 
Result so far: 95294.0
If we subtract 84 from 99, we get 15.
Bring next digit (7) of the dividend behind the 15 and repeat the process: 157 / 21

On to step 8:
21 goes into 157 7 times with a remainder of 10.
The number 7 becomes the next digit in our result. 
Result so far: 952947.0
If we take 147 away from 157, we end up 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.

Moving on to step 9:
The number 21 fits into 100 4 times, leaving a remainder of 16.
The next digit of our result is 4. 
Result so far: 952947.4
Subtract 84 from 100 to get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Moving on to step 10:
21 can be fit into 160 7 times, resulting in a remainder of 13.
Write down 7 as next digit of the result. 
Result so far: 952947.47
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.

Moving on to step 11:
When dividing 130 by 21, we get 6 with a remainder of 4.
The next digit of our result is 6. 
Result so far: 952947.476
If we subtract 126 from 130, we 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.

Going ahead to step 12:
21 goes into 40 1 times with a remainder of 19.
Use 1 as the next digit of our solution. 
Result so far: 952947.4761
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.

Advancing to step 13:
The number 21 fits into 190 9 times, leaving a remainder of 1.
Record the quotient 9 as the next digit in the result. 
Result so far: 952947.47619
Subtracting 189 from 190 leaves us with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Moving on to step 14:
If we divide 10 by 21, we get 0 and a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 952947.47619
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.

Going ahead to step 15:
When dividing 100 by 21, we get 4 with a remainder of 16.
The next digit of our result is 4. 
Result so far: 952947.4761904
If we take 84 away from 100, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

On to step 16:
If we divide 160 by 21, we get 7 and a remainder of 13.
Put 7 as the next digit of the answer. 
Result so far: 952947.47619047
Subtracting 147 from 160 leaves us 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.

The final result is 952947.47619047 with a remainder of 1.3e-08.