Let's dive into this subtraction. We'll start with 86917 and subtract 4371 from it.

Step 1: We'll start by subtracting the digit 1 and the borrow 0 from 7 in column 1 and get 6.
6 is the first digit of our result.

Step 2: We'll start by subtracting the digit 7 and the borrow 0 from 1 in column 2 and get -6.
We add -6 to 10 and get 4 as the next digit of the result.

Step 3: We'll start by subtracting the digit 3 and the borrow 1 from 9 in column 3 and get 5.
5 is the next digit of our result.

Step 4: We'll start by subtracting the digit 4 and the borrow 0 from 6 in column 4 and get 2.
2 is the next digit of our result.

Step 5: We'll start by subtracting the digit 0 and the borrow 0 from 8 in column 5 and get 8.
8 is the next digit of our result.

So, 86917 - 4371 = 82546.