Let's dive into this subtraction. We'll start with 574731 and subtract 73407 from it.

Step 1: We'll start by subtracting the digit 7 and the borrow 0 from 1 in column 1 and get -6.
We add -6 to 10 and get 4 as the first digit of the result.

Step 2: We'll start by subtracting the digit 0 and the borrow 1 from 3 in column 2 and get 2.
2 is the next digit of our result.

Step 3: We'll start by subtracting the digit 4 and the borrow 0 from 7 in column 3 and get 3.
3 is the next digit of our result.

Step 4: We'll start by subtracting the digit 3 and the borrow 0 from 4 in column 4 and get 1.
1 is the next digit of our result.

Step 5: We'll start by subtracting the digit 7 and the borrow 0 from 7 in column 5 and get 0.
0 is the next digit of our result.

Step 6: We'll start by subtracting the digit 0 and the borrow 0 from 5 in column 6 and get 5.
5 is the next digit of our result.

So, 574731 - 73407 = 501324.