12811

12811 is a natural number that follows 12810 and precedes 12812. In number theory, it is notable as a semiprime because it factors into two primes: 23 and 557. Consequently, its positive divisors are exactly 1, 23, 557, and 12811. It is an odd number and is not a perfect power (not a square, cube, etc.).

In different base representations, 12811 appears as follows: binary 11001000001011₂, hexadecimal 0x320B, and octal 31013₈. These representations illustrate common ways to encode the same value across numeral systems.

Modular arithmetic observations for 12811 include that it is congruent to 4 modulo 9 (since the sum of its digits, 1+2+8+1+1, is 13, and 13 ≡ 4 mod 9) and congruent to 1 modulo 3 and modulo 7. As a product of two primes, 12811 has exactly four positive divisors and serves as a straightforward example of a semiprime in elementary discussions of factorization.

Summary: 12811 is a composite, semiprime natural number with prime factors 23 and 557, four divisors, and multiple standard base representations (binary 11001000001011₂, hex 0x320B, octal 31013₈).