405839 has 4 divisors (see below), whose sum is σ = 463824. Its totient is φ = 347856.

The previous prime is 405829. The next prime is 405857. The reversal of 405839 is 938504.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 405839 - 2¹² = 401743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405829) 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, 28982 + ... + 28995.

It is an arithmetic number, because the mean of its divisors is an integer number (115956).

2⁴⁰⁵⁸³⁹ is an apocalyptic number.

405839 is a deficient number, since it is larger than the sum of its proper divisors (57985).

405839 is an equidigital number, since it uses as much as digits as its factorization.

405839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57984.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 405839 is about 637.0549426855. The cubic root of 405839 is about 74.0374171620.

The spelling of 405839 in words is "four hundred five thousand, eight hundred thirty-nine".