They do seem typical; the recruiter asked many of those same questions when I interviewed for a SRE position back in about 2004. I particularly enjoyed the bit count; I went back later and confirmed that the bit swiggling approach was faster on the machines I had handy. Large lookup tables have poor cache behavior.

On the other hand, the recruiter did not tell me whether I got the right answer (or I didn't miss any). It was pretty clearly a scripted initial phone screen with someone who wasn't a programmer.

Oh, and they didn't ask anything truly ridiculous like the QuickSort question.