DCCCXLIII

DCCCXLIII is the Roman numeral for the decimal value 843. It is formed by adding the values of D (500), CCC (300), XL (40), and III (3): 500 + 300 + 40 + 3 = 843.

Origin and formation: The numeral uses subtractive notation in the XL portion (40) to represent 40 succinctly rather than writing XXXX. The overall form DCCCXLIII follows standard Roman conventions for numbers in the 800s.

Historical usage: The year 843 AD is notable for the Treaty of Verdun, signed in August 843, which divided the Carolingian Empire into three kingdoms, shaping the political map of medieval Europe for centuries.

Mathematics: 843 factors as 3 × 281; since 281 is prime, 843 is a deficient number. It is an odd composite number.

Modern usage: Roman numerals like DCCCXLIII are still used for stylistic purposes, in monumental inscriptions, royal regnal numbers, and date annotations on monuments, though Arabic numerals are standard in most contemporary contexts.

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