"Four Hundred Thirty-One" refers to the number 431, which is an integer that follows 430 and precedes 432. It is an odd number and can be expressed in various forms, such as Roman numerals (CDXXXI) or in binary (110101111). In mathematics, 431 is classified as a prime number, meaning it has no positive divisors other than 1 and itself. This property makes it significant in number theory and various applications, including cryptography and computer science. Additionally, 431 can be found in different contexts, such as area codes or historical events.