XnView Software

The color of the attatched picture is HEX #717173 or RGB (113, 113, 115) (255 could be added for alpha channel).

If I inspect it with the color picker of XnView classic 2.43, it tells me RGB (71, 71, 73, 255) and HTML (#FF474749). That's wrong.

The # suggests that HTML is the HEX representative, which makes no sense with 8 digits instead of 6.

/edit
ok sorry, wait a second... much confusion going on right now
There is a new convention which allows 8 digits in CSS HEX color values, but then the transparency should be the last two digits, not the first. In the specs it's still a working draft.

/edit2
The colour of the attatched picture is indeed rgb(71,71,73)=#474749, so XnView is more or less showing correctly. Please put the alpha channel information for 8-digit HEX at the end instead of beginning.
The confusion was partly caused by the different color perception depending on the background color around the picture. Furthermore a color from my color scheme (#717173) has the same value numbers for hex as another from the scheme in rgb.

Wrong HTML value in “Display Colour Info” with 32-bit icons

So... if you don't change it from #AARRGGBB to #RRGGBBAA, then please relabel it and make it clear. Maybe separate it as suggested in the thread posted by XnTriq.

It's definitely not HTML and you can't use it in CSS, as the living standard is #RRGGBBAA there. And that's actually still a draft for oncoming CSS4 (as mentioned above), so it really really isn't html.

/edit
CSS3 specs (the current standard) even say

Unlike RGB values, there is no hexadecimal notation for an RGBA value.