There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.

Qenya 

yurasta

cardinal. twenty four

A specialized word for “twenty four” that was part of a duodecimal system of counting in notes from the 1930s, a combination of yú- “both” and -rasta “twelve”, so more literally “✱two twelves” (PE14/17 note #6).

-rasta

suffix. twelve

A suffix appearing in [ᴹQ.] yurasta “twenty four” in notes from the 1930s, probably meaning “✱double twelve” (PE14/17 note #6). Thus -rasta means “twelve”, as further evidenced by ᴹ√rasat “twelve” on the same page. This word seems to be the basis for a duodecimal numbering system, with -rasta taking the same role as -cainen “ten”; compare yucainen “twenty” = “✱double ten”. Presumably there are larger numbers like ✱nelerasta “thirty six = triple twelve” and ✱cantarasta “forty eight = quadruple twelve”, the duodecimal equivalents of thirty, forty, etc.

Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.