I have VS2015 Community installed. When I run is as administrator the UAC prompt says "devenv_80af265e-a92b-4324-ab32-c46fe27cebf2.exe".
What's shown to you in the UAC prompt is either the file name, or if the signer provided a description, that's what will be displayed instead.
This is the case with DevEnv.exe, MS signs with a description that includes the file name plus a "random" string of characters (not really sure how random it is between versions/computers).
If I use MS' SignTool to verify the file signature on DevEnv.exe and view the assigned description it reports (in part):
signtool.exe /v /pa /d devenv.exe)
Description URL: http://microsoft.com
Successfully verified: C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\devenv.exe
And low and behold the Description matches what the UAC prompt shows.
Why MS chose to use this format for the description of DevEnv.exe I'm not sure, nor can I find any reference to it.