308909 has 4 divisors (see below), whose sum is σ = 311904. Its totient is φ = 305916.

The previous prime is 308899. The next prime is 308923. The reversal of 308909 is 909803.

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 308909 - 2¹² = 304813 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (308929) 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, 1337 + ... + 1550.

It is an arithmetic number, because the mean of its divisors is an integer number (77976).

2³⁰⁸⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

308909 is a deficient number, since it is larger than the sum of its proper divisors (2995).

308909 is a wasteful number, since it uses less digits than its factorization.

308909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2994.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 308909 is about 555.7958258210. The cubic root of 308909 is about 67.5995057326.

It can be divided in two parts, 308 and 909, that multiplied together give a palindrome (279972).

The spelling of 308909 in words is "three hundred eight thousand, nine hundred nine".