18465881 has 4 divisors (see below), whose sum is σ = 21103872. Its totient is φ = 15827892.

The previous prime is 18465871. The next prime is 18465899. The reversal of 18465881 is 18856481.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18465881 - 2¹⁰ = 18464857 is a prime.

It is a super-2 number, since 2×18465881² = 681977522212322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18465841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1318985 + ... + 1318998.

It is an arithmetic number, because the mean of its divisors is an integer number (5275968).

Almost surely, 2^18465881 is an apocalyptic number.

It is an amenable number.

18465881 is a deficient number, since it is larger than the sum of its proper divisors (2637991).

18465881 is an equidigital number, since it uses as much as digits as its factorization.

18465881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2637990.

The product of its digits is 61440, while the sum is 41.

The square root of 18465881 is about 4297.1945499360. The cubic root of 18465881 is about 264.3159335580.

The spelling of 18465881 in words is "eighteen million, four hundred sixty-five thousand, eight hundred eighty-one".