664859 has 8 divisors (see below), whose sum is σ = 722400. Its totient is φ = 608256.

The previous prime is 664849. The next prime is 664879. The reversal of 664859 is 958466.

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 664859 - 2⁴ = 664843 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 (664849) 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, 2459 + ... + 2715.

It is an arithmetic number, because the mean of its divisors is an integer number (90300).

2⁶⁶⁴⁸⁵⁹ is an apocalyptic number.

664859 is a deficient number, since it is larger than the sum of its proper divisors (57541).

664859 is a wasteful number, since it uses less digits than its factorization.

664859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 469.

The product of its digits is 51840, while the sum is 38.

The square root of 664859 is about 815.3888642850. The cubic root of 664859 is about 87.2790178875.

The spelling of 664859 in words is "six hundred sixty-four thousand, eight hundred fifty-nine".