Diecinueve

Diecinueve is the Spanish cardinal number that represents the quantity of nineteen. It lies between eighteen and twenty and is used in counting, labeling, and arithmetic in Spanish. The word is written as diecinueve (one word) and is formed by combining diez (ten) with nueve (nine) and eliding the conjunction y in the intermediate form as diez y nueve → diecinueve.

In ordinal form, the 19th is decimonoveno. In Roman numerals, 19 is XIX; in binary 10011; in hexadecimal 13.

In mathematics, 19 is a prime number and an odd number. It is the eighth prime. It is not divisible by any integer other than 1 and 19. It is also the atomic number of potassium. This connection is sometimes noted in scientific contexts when listing elements by atomic number.

In culture and daily life, diecinueve appears in dates, measurements, and enumerations. For example, the 19th day of a month or the phrase diecinueve días denotes nineteen days. The term is used consistently across Spanish-speaking countries and follows standard Spanish numeration rules.

---