We look at the division of 20457075 by 646 
Let's see how many times 646 fits into 20457075.

Going ahead to step 1:
When dividing 2 by 646, we get 0 with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Include the next digit (0) from the dividend after 2, then repeat: 20 / 646

Moving on to step 2:
20 divided by 646 is 0 with a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 20 and we're left with 20.
Take the next digit (4) from the dividend and append it to 20, then repeat: 204 / 646

Moving on to step 3:
When dividing 204 by 646, we get 0 with a remainder of 204.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 204, we end up with 204.
Include the next digit (5) from the dividend after 204, then repeat: 2045 / 646

Moving on to step 4:
When dividing 2045 by 646, we get 3 with a remainder of 107.
Write down 3 as next digit of the result. 
Result so far: 3.0
If we take 1938 away from 2045, we end up with 107.
Bring next digit (7) of the dividend behind the 107 and repeat the process: 1077 / 646

Advancing to step 5:
When dividing 1077 by 646, we get 1 with a remainder of 431.
Use 1 as the next digit of our solution. 
Result so far: 31.0
If we subtract 646 from 1077, we get 431.
Grab the next digit (0) from the dividend, add it to 431, then carry on: 4310 / 646

Let's proceed to step 6:
4310 divided by 646 is 6 with a remainder of 434.
Use 6 as the next digit of our solution. 
Result so far: 316.0
If we take 3876 away from 4310, we end up with 434.
Take the next digit (7) from the dividend and append it to 434, then repeat: 4347 / 646

Let's proceed to step 7:
When dividing 4347 by 646, we get 6 with a remainder of 471.
The number 6 becomes the next digit in our result. 
Result so far: 3166.0
Subtract 3876 from 4347 to get 471.
Append the next digit (5) from the dividend to 471 and continue with: 4715 / 646

Let's proceed to step 8:
4715 divided by 646 is 7 with a remainder of 193.
Write down 7 as next digit of the result. 
Result so far: 31667.0
The remainder is 193 after subtracting 4522 from 4715.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1930, and continue the process.

Advancing to step 9:
When dividing 1930 by 646, we get 2 with a remainder of 638.
The number 2 becomes the next digit in our result. 
Result so far: 31667.2
If we subtract 1292 from 1930, we get 638.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6380, and continue the process.

Advancing to step 10:
646 goes into 6380 9 times with a remainder of 566.
The number 9 becomes the next digit in our result. 
Result so far: 31667.29
If we take 5814 away from 6380, we end up with 566.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5660, and continue the process.

Advancing to step 11:
The number 646 fits into 5660 8 times, leaving a remainder of 492.
Use 8 as the next digit of our solution. 
Result so far: 31667.298
Subtract 5168 from 5660 to get 492.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4920, and continue the process.

Moving on to step 12:
646 goes into 4920 7 times with a remainder of 398.
The number 7 becomes the next digit in our result. 
Result so far: 31667.2987
If we take 4522 away from 4920, we end up with 398.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3980, and continue the process.

On to step 13:
The number 646 fits into 3980 6 times, leaving a remainder of 104.
Use 6 as the next digit of our solution. 
Result so far: 31667.29876
Subtract 3876 from 3980 to get 104.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1040, and continue the process.

Going ahead to step 14:
1040 divided by 646 is 1 with a remainder of 394.
Record the quotient 1 as the next digit in the result. 
Result so far: 31667.298761
Subtract 646 from 1040 to get 394.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3940, and continue the process.

Going ahead to step 15:
646 can be fit into 3940 6 times, resulting in a remainder of 64.
The number 6 becomes the next digit in our result. 
Result so far: 31667.2987616
If we subtract 3876 from 3940, we get 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Going ahead to step 16:
640 divided by 646 is 0 with a remainder of 640.
The number 0 becomes the next digit in our result. 
Result so far: 31667.2987616
Subtract 0 from 640 to get 640.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6400, and continue the process.

In conclusion, the division gives 31667.2987616 with a balance of 6.4e-07.