549409 has 4 divisors (see below), whose sum is σ = 627904. Its totient is φ = 470916.

The previous prime is 549403. The next prime is 549421. The reversal of 549409 is 904945.

It is a happy number.

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 549409 - 2⁷ = 549281 is a prime.

It is a Duffinian number.

549409 is a lucky number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (549403) 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, 39237 + ... + 39250.

It is an arithmetic number, because the mean of its divisors is an integer number (156976).

2⁵⁴⁹⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

549409 is a deficient number, since it is larger than the sum of its proper divisors (78495).

549409 is an equidigital number, since it uses as much as digits as its factorization.

549409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78494.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 549409 is about 741.2212894946. The cubic root of 549409 is about 81.9027699441.

The spelling of 549409 in words is "five hundred forty-nine thousand, four hundred nine".