664025 has 6 divisors (see below), whose sum is σ = 823422. Its totient is φ = 531200.

The previous prime is 664019. The next prime is 664043. The reversal of 664025 is 520466.

It can be written as a sum of positive squares in 3 ways, for example, as 126736 + 537289 = 356^2 + 733^2 .

It is not a de Polignac number, because 664025 - 2⁴ = 664009 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 664025.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13256 + ... + 13305.

It is an arithmetic number, because the mean of its divisors is an integer number (137237).

2⁶⁶⁴⁰²⁵ is an apocalyptic number.

It is an amenable number.

664025 is a deficient number, since it is larger than the sum of its proper divisors (159397).

664025 is a wasteful number, since it uses less digits than its factorization.

664025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26571 (or 26566 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 664025 is about 814.8772913758. The cubic root of 664025 is about 87.2425083126.

The spelling of 664025 in words is "six hundred sixty-four thousand, twenty-five".