A pronoun has the type value card if it has numeric value (all values of integers, except un). This criterion is necessary and sufficient.
Test:
Given X a pronoun: If X has numeric value (all values of integers, except un), then it is a cardinal pronoun.
Examples:
Cardinal pronouns can be the head of a noun phrase, followed by a nominal modifier preposition phrase, introduced by `de'. Cardinal pronouns have this behavior in common with a range of indefinite pronouns.
Cardinal pronouns can be part of a discontinuous construction with the pronoun `en', where the pronoun `en' substitutes the prepositional phrase. Cardinal pronouns have this behavior in common with a range of indefinite pronouns.