18312911 has 4 divisors (see below), whose sum is σ = 18544800. Its totient is φ = 18081024.

The previous prime is 18312881. The next prime is 18312919. The reversal of 18312911 is 11921381.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18312911 - 2¹⁴ = 18296527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18312919) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115826 + ... + 115983.

It is an arithmetic number, because the mean of its divisors is an integer number (4636200).

Almost surely, 2^18312911 is an apocalyptic number.

18312911 is a deficient number, since it is larger than the sum of its proper divisors (231889).

18312911 is an equidigital number, since it uses as much as digits as its factorization.

18312911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231888.

The product of its digits is 432, while the sum is 26.

The square root of 18312911 is about 4279.3587136392. The cubic root of 18312911 is about 263.5840509507.

The spelling of 18312911 in words is "eighteen million, three hundred twelve thousand, nine hundred eleven".