CLXXII

CLXXII is the Roman numeral that represents the number 172. It is composed as C (100) + L (50) + XX (20) + II (2). This form uses additive notation, with no subtractive pattern needed to write 172.

In mathematics, 172 is an even composite number. Its prime factorization is 2^2 × 43, so its divisors are 1, 2, 4, 43, 86, and 172. It is not a prime, a square, or a cube, and it is part of the even numbers that lie between 171 and 173 in the natural number sequence.

Historically, 172 AD falls in the 2nd century of the Western calendar, during the Roman Empire and the reign of Marcus Aurelius. As a calendar year, it marks a point within the broader chronology of Roman imperial history; the specific events of that year are not universally singled out in general reference works. The notation CLXXII is also used in modern contexts to denote the 172nd item in enumerations, chapters, or volumes when Roman numerals are used for labeling.

In astronomy, the asteroid 172 Baucis is a main-belt object discovered by Johann Palisa in 1877. The name derives from Greek mythology, illustrating how numeric designations in science sometimes accompany mythological naming conventions.

Overall, CLXXII functions as both a precise numeric value and a stylistic Roman numeral designation applicable in arithmetic, chronology, and labeling systems.