We look at the division of 40621495 by 21 
Let's see how many times 21 fits into 40621495.

On to step 1:
The number 21 fits into 4 0 times, leaving a remainder of 4.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Grab the next digit (0) from the dividend, add it to 4, then carry on: 40 / 21

Advancing to step 2:
21 goes into 40 1 times with a remainder of 19.
Write down 1 as next digit of the result. 
Result so far: 1.0
Subtracting 21 from 40 leaves us with 19.
Bring next digit (6) of the dividend behind the 19 and repeat the process: 196 / 21

Going ahead to step 3:
The number 21 fits into 196 9 times, leaving a remainder of 7.
Use 9 as the next digit of our solution. 
Result so far: 19.0
Deduct 189 from 196 and we're left with 7.
Grab the next digit (2) from the dividend, add it to 7, then carry on: 72 / 21

On to step 4:
21 goes into 72 3 times with a remainder of 9.
Record the quotient 3 as the next digit in the result. 
Result so far: 193.0
If we subtract 63 from 72, we get 9.
Bring next digit (1) of the dividend behind the 9 and repeat the process: 91 / 21

Let's proceed to step 5:
91 divided by 21 is 4 with a remainder of 7.
Use 4 as the next digit of our solution. 
Result so far: 1934.0
Deduct 84 from 91 and we're left with 7.
Fetch the next digit (4) from the dividend, attach it to 7 and continue: 74 / 21

Step 6:
If we divide 74 by 21, we get 3 and a remainder of 11.
The next digit of our result is 3. 
Result so far: 19343.0
If we subtract 63 from 74, we get 11.
Bring next digit (9) of the dividend behind the 11 and repeat the process: 119 / 21

Advancing to step 7:
When dividing 119 by 21, we get 5 with a remainder of 14.
Use 5 as the next digit of our solution. 
Result so far: 193435.0
If we subtract 105 from 119, we get 14.
Grab the next digit (5) from the dividend, add it to 14, then carry on: 145 / 21

Advancing to step 8:
21 can be fit into 145 6 times, resulting in a remainder of 19.
Record the quotient 6 as the next digit in the result. 
Result so far: 1934356.0
The remainder is 19 after subtracting 126 from 145.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Moving on to step 9:
21 goes into 190 9 times with a remainder of 1.
The next digit of our result is 9. 
Result so far: 1934356.9
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.

Advancing to step 10:
21 can be fit into 10 0 times, resulting in a remainder of 10.
Use 0 as the next digit of our solution. 
Result so far: 1934356.9
Subtracting 0 from 10 leaves us 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.

Let's proceed to step 11:
21 can be fit into 100 4 times, resulting in a remainder of 16.
Put 4 as the next digit of the answer. 
Result so far: 1934356.904
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.

Let's proceed to step 12:
When dividing 160 by 21, we get 7 with a remainder of 13.
The number 7 becomes the next digit in our result. 
Result so far: 1934356.9047
Deduct 147 from 160 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.

Going ahead to step 13:
The number 21 fits into 130 6 times, leaving a remainder of 4.
Use 6 as the next digit of our solution. 
Result so far: 1934356.90476
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.

Step 14:
The number 21 fits into 40 1 times, leaving a remainder of 19.
The next digit of our result is 1. 
Result so far: 1934356.904761
If we subtract 21 from 40, we get 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Moving on to step 15:
The number 21 fits into 190 9 times, leaving a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 1934356.9047619
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.

Going ahead to step 16:
21 can be fit into 10 0 times, resulting in a remainder of 10.
Record the quotient 0 as the next digit in the result. 
Result so far: 1934356.9047619
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.

Our division results in 1934356.9047619 with a remaining 1e-08.