18494409 has 4 divisors (see below), whose sum is σ = 24659216. Its totient is φ = 12329604.

The previous prime is 18494401. The next prime is 18494501. The reversal of 18494409 is 90449481.

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 not a de Polignac number, because 18494409 - 2³ = 18494401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18494401) 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, 3082399 + ... + 3082404.

It is an arithmetic number, because the mean of its divisors is an integer number (6164804).

Almost surely, 2^18494409 is an apocalyptic number.

It is an amenable number.

18494409 is a deficient number, since it is larger than the sum of its proper divisors (6164807).

18494409 is an equidigital number, since it uses as much as digits as its factorization.

18494409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6164806.

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 18494409 is about 4300.5126438600. The cubic root of 18494409 is about 264.4519777073.

The spelling of 18494409 in words is "eighteen million, four hundred ninety-four thousand, four hundred nine".