306409 has 4 divisors (see below), whose sum is σ = 308880. Its totient is φ = 303940.

The previous prime is 306407. The next prime is 306419. The reversal of 306409 is 904603.

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, and also an emirpimes, since its reverse is a distinct semiprime: 904603 = 7 ⋅129229.

It is a cyclic number.

It is not a de Polignac number, because 306409 - 2¹ = 306407 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 306409.

It is not an unprimeable number, because it can be changed into a prime (306407) 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, 1039 + ... + 1300.

It is an arithmetic number, because the mean of its divisors is an integer number (77220).

2³⁰⁶⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

306409 is a deficient number, since it is larger than the sum of its proper divisors (2471).

306409 is a wasteful number, since it uses less digits than its factorization.

306409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2470.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 306409 is about 553.5422296447. The cubic root of 306409 is about 67.4166506659.

The spelling of 306409 in words is "three hundred six thousand, four hundred nine".