A bit of a disappointment, and, really, it had much less to do with prime numbers than I had thought. There is a lot that can be made of analogies between prime numbers and relationships, but sadly, this book didn’t really dive into any of that. Aside from that, the characters were unsympathetic, the plot dry and plodding, and really, just too depressing to be enjoyable. Serves me right for picking up a book just for its title!