664907 has 4 divisors (see below), whose sum is σ = 693840. Its totient is φ = 635976.

The previous prime is 664891. The next prime is 664933. The reversal of 664907 is 709466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 664907 - 2⁴ = 664891 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (664967) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14432 + ... + 14477.

It is an arithmetic number, because the mean of its divisors is an integer number (173460).

2⁶⁶⁴⁹⁰⁷ is an apocalyptic number.

664907 is a deficient number, since it is larger than the sum of its proper divisors (28933).

664907 is a wasteful number, since it uses less digits than its factorization.

664907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28932.

The product of its (nonzero) digits is 9072, while the sum is 32.

The square root of 664907 is about 815.4182975627. The cubic root of 664907 is about 87.2811182286.

The spelling of 664907 in words is "six hundred sixty-four thousand, nine hundred seven".