t h i r t e e n
The 13 letters RGAOIWUOTFINY do not spell a word. They spell the phrase "waiting for you" (among others of less grammatical sense). The longest single word is "figuration."
13 in word form is: thirteen.thirteen
The letters do not spell any 13 letter word. However they can be used to spell the 9 letter word instincts.
Thirtieth.
Fourteenth.
fourteen
Sixteen.
Twelfth.
53.5 in word form is: fifty-three and five tenths.
4.94 in word form = four and ninety-four hundredths.
The letters spell the word card.
You can't spell any 13 letter words from just 12 letters. You need the final S to spell "procrastinate."