My Erdős number is 2 (which is, of course, the lowest it will ever be).
Three of my co-authors have Erdős numbers of 1. Listed in the order in which they became my co-authors:
My first collaboration was with Andrey Feuerverger, which gave me my first finite Erdős number of 4. My papers with Kevin O'Bryant bound my Erdős number from above by 3. At the moment, if all references to me in the universe were magically erased without warning, the only person whose Erdős number would change (besides my own) is Scott Sitar, who would go from Erdős number 3 to Erdős number ∞.
Many thanks to Jerry Grossman et al. for maintaining the Erdős Number Project home page.