Hallatan was made regent of Númenor in the year II 883, so we know that he lived to at least the age of 172. Hallatan was a descendant of Vardamir Nólimon, the second King of Númenor, and this royal ancestry meant that he could expect a lifespan of somewhere between three and four centuries.
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Hallatan's name almost certainly contains Hall- from the root khal- meaning 'high' or 'exalted'. Hall- can also come from a different root, skal-, 'veiled' or 'hidden', though this alternative can surely be discounted in Hallatan's case.