Can 余 (more than) go after the measure word? I've just learned a new formal word 余 and I'm trying to understand it's placement. I know that roughly it means 多 but in a more formal way. If for example, I was saying "more than 500 people" I think I could say both

五百多人， 
and
五百人多 （correct me if I'm wrong on this one) 

However, could I say 

五百余人？ 
五百人余？
五百多人 is correct and colloquial.
五百余人 is correct and formal.
五百人多 is not correct.
五百人余 is not grammatical in modern Mandarin but contextually valid in ancient Chinese. It may appear a lot in ancient stories written in vernacular language.