405309 has 8 divisors (see below), whose sum is σ = 544320. Its totient is φ = 268256.

The previous prime is 405299. The next prime is 405323. The reversal of 405309 is 903504.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 405309 - 2⁵ = 405277 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405709) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97 + ... + 905.

It is an arithmetic number, because the mean of its divisors is an integer number (68040).

2⁴⁰⁵³⁰⁹ is an apocalyptic number.

It is an amenable number.

405309 is a deficient number, since it is larger than the sum of its proper divisors (139011).

405309 is a wasteful number, since it uses less digits than its factorization.

405309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 979.

The product of its (nonzero) digits is 540, while the sum is 21.

The square root of 405309 is about 636.6388301070. The cubic root of 405309 is about 74.0051737313.

The spelling of 405309 in words is "four hundred five thousand, three hundred nine".