Yes it should be hyphenated.
This is in two words, "twenty fourth," hyphenated in the US as twenty-fourth (24th).
It is neither. The word is hyphenated, like so: twenty-third.
21st is usually hyphenated when spelt. Dictionaries list it as 'twenty-first'. However, as a book/article title, or in company names, it is sometimes written as Twenty First ... as in 'Twenty First Century Poets', but, as this could be interpreted as meaning a book about 1st century poets, a hyphen would remove any ambiguity e.g. written as 'Twenty-first Century Poets' or 'Twenty-First Century Poets' (unless, of course, the book is actually about 1st century poets, in which case a better title would be 'Twenty First-Century Poets'!)
twenty-seven
The spelling would be "one twenty-fourth" or 1/24.(the denominator is separately hyphenated, as in twenty-one twenty-fourths, 21/24)
The second word should not be capitalized
Any two or three word adjective should be hyphenated ONLY when used as an adjective. Example, "It was his thirty-second birthday." "There was a thirty second delay in rebroadcasting Carl's speech."
The number 428 is "four hundred twenty-eight." (It is hyphenated when used as an adjective in English.)
The Twenty-Second Day was created in 2007.
The Twenty-Second Day has 100 pages.
July 22nd