8981

8981 is a natural number that follows 8980 and precedes 8982. In mathematics, it is an odd composite number classified as a semiprime, meaning it is the product of exactly two primes: 7 and 1283.

Its prime factorization is 7 × 1283, with 1283 being a prime number. Because the two prime factors are distinct, 8981 is square-free and has four positive divisors: 1, 7, 1283, and 8981.

In various numeral systems, 8981 has the representations 10001100010101 in binary, 2315 in hexadecimal (base 16), and 21425 in octal (base 8). These alternate representations illustrate its numerical structure across bases.

From a number-theoretic perspective, 8981 is congruent to 1 modulo 4, but it cannot be expressed as a sum of two squares. This is due to the presence of a prime factor congruent to 3 modulo 4 (namely 7) with odd exponent in its factorization, which prevents such a representation.

Contextually, semiprimes like 8981 are of interest in mathematics as a simple yet nontrivial class of composite numbers. They also appear in discussions of factorization and cryptographic concepts, since the difficulty of factoring larger semiprimes underpins certain cryptographic systems. While 8981 itself is small and primarily of theoretical interest, it serves as a concrete example of a semiprime and of the properties that arise from its factorization.