406389 has 4 divisors (see below), whose sum is σ = 541856. Its totient is φ = 270924.

The previous prime is 406381. The next prime is 406397. The reversal of 406389 is 983604.

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 an interprime number because it is at equal distance from previous prime (406381) and next prime (406397).

It is not a de Polignac number, because 406389 - 2³ = 406381 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (406381) 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, 67729 + ... + 67734.

It is an arithmetic number, because the mean of its divisors is an integer number (135464).

2⁴⁰⁶³⁸⁹ is an apocalyptic number.

It is an amenable number.

406389 is a deficient number, since it is larger than the sum of its proper divisors (135467).

406389 is a wasteful number, since it uses less digits than its factorization.

406389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135466.

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 406389 is about 637.4864704447. The cubic root of 406389 is about 74.0708476589.

The spelling of 406389 in words is "four hundred six thousand, three hundred eighty-nine".