CCCLXV

CCCLXV is the Roman numeral for the integer 365. It is formed by combining CCC (300) + LX (60) + V (5). In Roman numerals, numerals are written in descending order and added together, so CCCLXV is an additive representation rather than using subtractive notation, which appears in other numbers such as CD for 400 or IV for 4.

The number 365 is notable as the number of days in a common year in the Gregorian calendar. A leap year adds one day every four years, making a total of 366 days. Beyond calendrical use, 365 is a composite number, equal to 5 multiplied by 73. As an approximate count of days in the solar year, it has influenced historical timekeeping and calendars, though modern systems use more precise values for long-term calculations.

In modern contexts, Roman numerals like CCCLXV are encountered in a variety of ceremonial, decorative, and traditional uses. They appear on monuments and inscriptions, clock faces, book chapter headings, and in the enumeration of monarchs or popes. While the decimal system predominates for everyday measurement and arithmetic, Roman numerals retain cultural and historical significance and are still taught and used in specific contexts to convey formality or antiquity.