Full Idea
Essentialism is not verified by the observation that numbers have interesting essential properties, since they are properties of classes and so are entities of a higher logical type than individuals.
Gist of Idea
Only individuals have essences, so numbers (as a higher type based on classes) lack them
Source
Alan McMichael (The Epistemology of Essentialist Claims [1986], Intro)
Book Reference
'Midwest Studs XI:Essentialism', ed/tr. French,Uehling,Wettstein [Minnesota 1986], p.33
A Reaction
This relies on a particular view of number (which might be challenged), but is interesting when it comes to abstract entities having essences. Only ur-elements in set theory could have essences, it seems. Why? Rising in type destroys essence?