664065 has 16 divisors (see below), whose sum is σ = 1180800. Its totient is φ = 354096.

The previous prime is 664061. The next prime is 664067. The reversal of 664065 is 560466.

It is not a de Polignac number, because 664065 - 2² = 664061 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (664061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2325 + ... + 2594.

It is an arithmetic number, because the mean of its divisors is an integer number (73800).

2⁶⁶⁴⁰⁶⁵ is an apocalyptic number.

It is an amenable number.

664065 is a deficient number, since it is larger than the sum of its proper divisors (516735).

664065 is a wasteful number, since it uses less digits than its factorization.

664065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4933 (or 4927 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 664065 is about 814.9018345789. The cubic root of 664065 is about 87.2442600691.

The spelling of 664065 in words is "six hundred sixty-four thousand, sixty-five".