664635023 has 4 divisors (see below), whose sum is σ = 715760808. Its totient is φ = 613509240.

The previous prime is 664635017. The next prime is 664635053. The reversal of 664635023 is 320536466.

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 664635023 - 2⁴ = 664635007 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 (664635053) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25562873 + ... + 25562898.

It is an arithmetic number, because the mean of its divisors is an integer number (178940202).

Almost surely, 2^664635023 is an apocalyptic number.

664635023 is a deficient number, since it is larger than the sum of its proper divisors (51125785).

664635023 is a wasteful number, since it uses less digits than its factorization.

664635023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51125784.

The product of its (nonzero) digits is 77760, while the sum is 35.

The square root of 664635023 is about 25780.5163447127. The cubic root of 664635023 is about 872.6921596553.

The spelling of 664635023 in words is "six hundred sixty-four million, six hundred thirty-five thousand, twenty-three".