52455934 ÷ 21 
Let's see how many times 21 fits into 52455934.

On to step 1:
If we divide 5 by 21, we get 0 and a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 5 after subtracting 0 from 5.
Include the next digit (2) from the dividend after 5, then repeat: 52 / 21

Advancing to step 2:
If we divide 52 by 21, we get 2 and a remainder of 10.
Write down 2 as next digit of the result. 
Result so far: 2.0
Subtract 42 from 52 to get 10.
Take the next digit (4) from the dividend and append it to 10, then repeat: 104 / 21

Advancing to step 3:
The number 21 fits into 104 4 times, leaving a remainder of 20.
Use 4 as the next digit of our solution. 
Result so far: 24.0
Deduct 84 from 104 and we're left with 20.
Grab the next digit (5) from the dividend, add it to 20, then carry on: 205 / 21

Moving on to step 4:
If we divide 205 by 21, we get 9 and a remainder of 16.
The number 9 becomes the next digit in our result. 
Result so far: 249.0
If we take 189 away from 205, we end up with 16.
Append the next digit (5) from the dividend to 16 and continue with: 165 / 21

Step 5:
21 goes into 165 7 times with a remainder of 18.
Use 7 as the next digit of our solution. 
Result so far: 2497.0
The remainder is 18 after subtracting 147 from 165.
Grab the next digit (9) from the dividend, add it to 18, then carry on: 189 / 21

Going ahead to step 6:
189 divided by 21 is 9 with a remainder of 0.
The next digit of our result is 9. 
Result so far: 24979.0
Subtract 189 from 189 to get 0.
Grab the next digit (3) from the dividend, add it to 0, then carry on: 3 / 21

Going ahead to step 7:
If we divide 3 by 21, we get 0 and a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 249790.0
Subtract 0 from 3 to get 3.
Include the next digit (4) from the dividend after 3, then repeat: 34 / 21

Advancing to step 8:
34 divided by 21 is 1 with a remainder of 13.
Write down 1 as next digit of the result. 
Result so far: 2497901.0
If we take 21 away from 34, we end up 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.

Step 9:
130 divided by 21 is 6 with a remainder of 4.
Write down 6 as next digit of the result. 
Result so far: 2497901.6
If we take 126 away from 130, we end up 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.

Moving on to step 10:
40 divided by 21 is 1 with a remainder of 19.
The next digit of our result is 1. 
Result so far: 2497901.61
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.

Step 11:
21 can be fit into 190 9 times, resulting in a remainder of 1.
The number 9 becomes the next digit in our result. 
Result so far: 2497901.619
If we subtract 189 from 190, we get 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 12:
When dividing 10 by 21, we get 0 with a remainder of 10.
Use 0 as the next digit of our solution. 
Result so far: 2497901.619
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 13:
The number 21 fits into 100 4 times, leaving a remainder of 16.
Use 4 as the next digit of our solution. 
Result so far: 2497901.61904
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 14:
If we divide 160 by 21, we get 7 and a remainder of 13.
Use 7 as the next digit of our solution. 
Result so far: 2497901.619047
The remainder is 13 after subtracting 147 from 160.
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 15:
When dividing 130 by 21, we get 6 with a remainder of 4.
The number 6 becomes the next digit in our result. 
Result so far: 2497901.6190476
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.

Advancing to step 16:
If we divide 40 by 21, we get 1 and a remainder of 19.
Record the quotient 1 as the next digit in the result. 
Result so far: 2497901.61904761
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.

After the division, we end up with 2497901.61904761 and a remainder of 1.9e-08.