We're dividing 871573 by 45 
We want to figure out the number of times 871573 can be divided by 45.

Moving on to step 1:
The number 45 fits into 8 0 times, leaving a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Fetch the next digit (7) from the dividend, attach it to 8 and continue: 87 / 45

Moving on to step 2:
The number 45 fits into 87 1 times, leaving a remainder of 42.
Write down 1 as next digit of the result. 
Result so far: 1.0
Deduct 45 from 87 and we're left with 42.
Take the next digit (1) from the dividend and append it to 42, then repeat: 421 / 45

Advancing to step 3:
421 divided by 45 is 9 with a remainder of 16.
Put 9 as the next digit of the answer. 
Result so far: 19.0
Subtracting 405 from 421 leaves us with 16.
Bring next digit (5) of the dividend behind the 16 and repeat the process: 165 / 45

Let's proceed to step 4:
When dividing 165 by 45, we get 3 with a remainder of 30.
Use 3 as the next digit of our solution. 
Result so far: 193.0
If we take 135 away from 165, we end up with 30.
Include the next digit (7) from the dividend after 30, then repeat: 307 / 45

Moving on to step 5:
45 can be fit into 307 6 times, resulting in a remainder of 37.
Write down 6 as next digit of the result. 
Result so far: 1936.0
Subtracting 270 from 307 leaves us with 37.
Grab the next digit (3) from the dividend, add it to 37, then carry on: 373 / 45

Step 6:
45 goes into 373 8 times with a remainder of 13.
The number 8 becomes the next digit in our result. 
Result so far: 19368.0
If we subtract 360 from 373, we 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.

Advancing to step 7:
If we divide 130 by 45, we get 2 and a remainder of 40.
Record the quotient 2 as the next digit in the result. 
Result so far: 19368.2
If we take 90 away from 130, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Going ahead to step 8:
When dividing 400 by 45, we get 8 with a remainder of 40.
Write down 8 as next digit of the result. 
Result so far: 19368.28
If we take 360 away from 400, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Going ahead to step 9:
400 divided by 45 is 8 with a remainder of 40.
Use 8 as the next digit of our solution. 
Result so far: 19368.288
If we take 360 away from 400, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

The quotient of the division is 19368.288, and the remainder is 0.004.