21 in Roman Numerals
The number 21 is written XXI in Roman numerals. Reading left to right and adding the values gives 10 + 10 + 1 = 21. Roman numerals use seven letters — I (1), V (5), X (10), L (50), C (100), D (500) and M (1000) — with a smaller letter before a larger one meaning subtraction (IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900).
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Frequently asked
What is 21 in Roman numerals?
21 in Roman numerals is XXI.
How is 21 written in Roman numerals?
21 is written XXI, which breaks down as 10 + 10 + 1 = 21.
Is there a Roman numeral for zero?
No. The Roman system has no symbol for zero, which is one reason it was eventually replaced for calculation.