unlimited number of values gets really big
Put the relationship the other way round, ie let every inhabitant be a separate entity that has an entity reference to a city. 

Then you can still display them on a city content view by using an embedded view, such as EVA or Display Suite dynamic field, or using Panels. You can even embed it via a preprocess_node function using view_embed_view, and have pagination on it.

And views will use the inverse relationship just fine.

Look at the wiki entry for Cardinality (data modeling) for more information on this principle.