Figures of Merit (Erdős number) in Resume/CV

I've noticed recently that colleagues, friends, and others seeking employment, have shown, among other things, their Erdős number on their resume/CV. I've also seen some put down their h-index, or their publication with the most citations (the running tally of citations for that publication), or the Impact Factor journal that they have ever published in, etc.

I know there is a question on just h-index in a CV/resume (so please do not mark as duplicate), but this is a broader question about other figures of merit, especially Erdős number.

I realize that having a CV/resume that stands out is important and can give an edge to getting that coveted position, but is listing these types of things appropriate?