404639 has 8 divisors (see below), whose sum is σ = 429792. Its totient is φ = 380160.

The previous prime is 404597. The next prime is 404671. The reversal of 404639 is 936404.

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 404639 - 2¹⁶ = 339103 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 (404699) 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 7 ways as a sum of consecutive naturals, for example, 1559 + ... + 1799.

It is an arithmetic number, because the mean of its divisors is an integer number (53724).

2⁴⁰⁴⁶³⁹ is an apocalyptic number.

404639 is a deficient number, since it is larger than the sum of its proper divisors (25153).

404639 is a wasteful number, since it uses less digits than its factorization.

404639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337.

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 404639 is about 636.1124114494. The cubic root of 404639 is about 73.9643729159.

The spelling of 404639 in words is "four hundred four thousand, six hundred thirty-nine".