The most common practice is to distinguish "een" (indefinite article, which, as a clitic, bears no stress) from "n" (the cardinal number one).
en.wikipedia.org The quantity -- a cardinal number -- is associated with the set, and is invariant under the process of counting.
en.wikipedia.org Formal-ontological categories relate objects and include notions such as set, cardinal number, ordinal number, part and whole, relation, and so on.
en.wikipedia.org From 5th to 99th, ordinals are formed simply by declining the corresponding cardinal number as a regular adjective.
en.wikipedia.org For example, aleph-null is the cardinality of the infinite set of natural numbers, and aleph-one is the next greatest cardinal number.
en.wikipedia.org