1888. MDCCCLXXXVIII has 13 characters and is the only 13 character Roman number between 1 and 2000.
888. The next longest Roman number is 2888. MMDCCCLXXXVIII has 14 characters. Also between 2001 and 3000 there are another six 13 character numbers.
There are only two common, everyday words which are valid Roman numbers - I (1) and mix (1009).
But there are seven words altogether - div (504), dix (509), I (1), li (51), mi (1001), mix (1009), and xi (11). The Scrabble Dictionary (third edition) also allows di (501), which is really just a prefix. There are also six common abbreviations which are valid Roman numbers - cc (200), CD (400), cv (105), DC (600), MC (1100), and MD (1500). And two trade names - CDi (401) and Clix (159). Also, the name Liv (54) as in Liv Ullman and Di (501) as in Princess Di.
There may be more. Please let me know if you find any.
8. They are:- MDCLXVI (1666), MDCLXIV (1664), MDCXLVI (1646), MDCXLIV (1644), MCDLXVI (1466), MCDLXIV (1464), MCDXLVI (1446), and MCDXLIV (1444).
MDCLXVI (1666) and MCDXLIV (1444)
There is no simple answer to this question. The bigger the dictionary the more you find. Allowing only complete words which are not proper nouns, I have found 35 using both the Oxford English Dictionary, second edition 1989 (OEDII) and the Scrabble Dictionary, based on Chamber's Dictionary, and now in its third edition. If you count common abbreviations, allow proper nouns, and include prefixes then I get up to 52. The longest contains 6 letters. But there may be more. Please send me your lists and, for really obscure words, why you think they are valid.
civic, civil, immix, livid, mimic, villi, and vivid. The Scrabble Dictionary, 3rd edition, also allows dilli which OEDII gives as an obsolete and rare prefix, as in dilli-darling, an affectionate expansion of darling.
Five. Civic - CCVII, civil - CLVII, immix - MMXII, livid - DLVII, and mimic - MMCII. Villi and vivid (and dilli) cannot be rearranged as valid Roman numbers.
mimic (2102) and civil (157)
I married Lisa in Acton church
Show all the Roman numerals
I MarrIeD LIsa In aCton ChurCh