151

151 is a natural number that follows 150 and precedes 152. It is an odd prime and, in decimal notation, a palindromic number, meaning it reads the same forward and backward. As a prime, 151 has no positive divisors other than 1 and itself, and it is the 36th prime.

In other numeral systems, 151 has the representations 10010111 in binary, 0x97 in hexadecimal, and 0o227 in octal. Its mathematical properties include being non-square and non-triangular, with no simple expression as a product or power of smaller integers beyond 1 and 151.

In Roman numerals, 151 is written as CLI. The notation is sometimes used in historical dating and document references to denote the year 151 CE, though context and calendar system are essential for interpretation.

Beyond pure mathematics, 151 does not have a single widely recognized significance and is mainly encountered in examples of prime and palindromic numbers, or as a numeric label in various administrative, cataloging, or coding schemes. As a prime palindrome, it is sometimes cited in discussions of number patterns and recreational number theory.