We're dividing 20903995 by 645 
We're looking to find how many times 645 goes into 20903995.

Let's proceed to step 1:
645 goes into 2 0 times with a remainder of 2.
The number 0 becomes the next digit in our 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 / 645

Advancing to step 2:
When dividing 20 by 645, we get 0 with a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 20, we end up with 20.
Bring next digit (9) of the dividend behind the 20 and repeat the process: 209 / 645

Let's proceed to step 3:
645 can be fit into 209 0 times, resulting in a remainder of 209.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 209, we get 209.
Take the next digit (0) from the dividend and append it to 209, then repeat: 2090 / 645

Step 4:
When dividing 2090 by 645, we get 3 with a remainder of 155.
The next digit of our result is 3. 
Result so far: 3.0
Subtract 1935 from 2090 to get 155.
Bring next digit (3) of the dividend behind the 155 and repeat the process: 1553 / 645

Step 5:
645 can be fit into 1553 2 times, resulting in a remainder of 263.
The next digit of our result is 2. 
Result so far: 32.0
Subtracting 1290 from 1553 leaves us with 263.
Bring next digit (9) of the dividend behind the 263 and repeat the process: 2639 / 645

Going ahead to step 6:
645 can be fit into 2639 4 times, resulting in a remainder of 59.
The number 4 becomes the next digit in our result. 
Result so far: 324.0
The remainder is 59 after subtracting 2580 from 2639.
Fetch the next digit (9) from the dividend, attach it to 59 and continue: 599 / 645

Going ahead to step 7:
645 goes into 599 0 times with a remainder of 599.
Put 0 as the next digit of the answer. 
Result so far: 3240.0
If we subtract 0 from 599, we get 599.
Append the next digit (5) from the dividend to 599 and continue with: 5995 / 645

Let's proceed to step 8:
645 can be fit into 5995 9 times, resulting in a remainder of 190.
Put 9 as the next digit of the answer. 
Result so far: 32409.0
Deduct 5805 from 5995 and we're left with 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1900, and continue the process.

Advancing to step 9:
When dividing 1900 by 645, we get 2 with a remainder of 610.
Write down 2 as next digit of the result. 
Result so far: 32409.2
Subtract 1290 from 1900 to get 610.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6100, and continue the process.

On to step 10:
If we divide 6100 by 645, we get 9 and a remainder of 295.
Write down 9 as next digit of the result. 
Result so far: 32409.29
If we subtract 5805 from 6100, we get 295.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2950, and continue the process.

Advancing to step 11:
If we divide 2950 by 645, we get 4 and a remainder of 370.
The next digit of our result is 4. 
Result so far: 32409.294
Subtracting 2580 from 2950 leaves us with 370.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3700, and continue the process.

Going ahead to step 12:
If we divide 3700 by 645, we get 5 and a remainder of 475.
The next digit of our result is 5. 
Result so far: 32409.2945
The remainder is 475 after subtracting 3225 from 3700.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4750, and continue the process.

On to step 13:
645 goes into 4750 7 times with a remainder of 235.
The number 7 becomes the next digit in our result. 
Result so far: 32409.29457
Deduct 4515 from 4750 and we're left with 235.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2350, and continue the process.

Step 14:
645 goes into 2350 3 times with a remainder of 415.
Write down 3 as next digit of the result. 
Result so far: 32409.294573
Deduct 1935 from 2350 and we're left with 415.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4150, and continue the process.

On to step 15:
645 can be fit into 4150 6 times, resulting in a remainder of 280.
The number 6 becomes the next digit in our result. 
Result so far: 32409.2945736
If we subtract 3870 from 4150, we get 280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2800, and continue the process.

Step 16:
645 goes into 2800 4 times with a remainder of 220.
Record the quotient 4 as the next digit in the result. 
Result so far: 32409.29457364
Subtracting 2580 from 2800 leaves us with 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2200, and continue the process.

The final result is 32409.29457364 with a remainder of 2.2e-07.