Does any one know, have a list of the various attributes/arguments that the userProfileLookup can return?

I am using this in a Calculated Value field but appears to be limited to certain values. I cannot pull phone number. I have used 'WorkPhone', telephoneNumber', 'Phone', etc.  I can see my phone number in my Profile under Direct Dial.  However using 'DirectDial' does not return anything either.  I was hoping to learn what this function actually does support or if another factor is causing me to get no value.  I can get name, job title, email and office only phone number is an issue.