861773 ÷ 45 
Our goal is to divide 861773 by 45.

Step 1:
45 can be fit into 8 0 times, resulting in a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Bring next digit (6) of the dividend behind the 8 and repeat the process: 86 / 45

Moving on to step 2:
45 goes into 86 1 times with a remainder of 41.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Deduct 45 from 86 and we're left with 41.
Bring next digit (1) of the dividend behind the 41 and repeat the process: 411 / 45

Going ahead to step 3:
45 goes into 411 9 times with a remainder of 6.
Use 9 as the next digit of our solution. 
Result so far: 19.0
If we subtract 405 from 411, we get 6.
Grab the next digit (7) from the dividend, add it to 6, then carry on: 67 / 45

Moving on to step 4:
When dividing 67 by 45, we get 1 with a remainder of 22.
Use 1 as the next digit of our solution. 
Result so far: 191.0
If we subtract 45 from 67, we get 22.
Fetch the next digit (7) from the dividend, attach it to 22 and continue: 227 / 45

Moving on to step 5:
227 divided by 45 is 5 with a remainder of 2.
The number 5 becomes the next digit in our result. 
Result so far: 1915.0
Subtracting 225 from 227 leaves us with 2.
Append the next digit (3) from the dividend to 2 and continue with: 23 / 45

Step 6:
When dividing 23 by 45, we get 0 with a remainder of 23.
Put 0 as the next digit of the answer. 
Result so far: 19150.0
If we subtract 0 from 23, we get 23.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

Let's proceed to step 7:
45 can be fit into 230 5 times, resulting in a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 19150.5
Subtracting 225 from 230 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Moving on to step 8:
50 divided by 45 is 1 with a remainder of 5.
The number 1 becomes the next digit in our result. 
Result so far: 19150.51
If we subtract 45 from 50, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 9:
50 divided by 45 is 1 with a remainder of 5.
The number 1 becomes the next digit in our result. 
Result so far: 19150.511
Deduct 45 from 50 and we're left with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

The final outcome is 19150.511, with a leftover of 0.0005.