664401823 has 16 divisors (see below), whose sum is σ = 715968000. Its totient is φ = 614561472.

The previous prime is 664401811. The next prime is 664401833. The reversal of 664401823 is 328104466.

It is a de Polignac number, because none of the positive numbers 2^k-664401823 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 (664401833) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 587923 + ... + 589051.

It is an arithmetic number, because the mean of its divisors is an integer number (44748000).

Almost surely, 2^664401823 is an apocalyptic number.

664401823 is a deficient number, since it is larger than the sum of its proper divisors (51566177).

664401823 is a wasteful number, since it uses less digits than its factorization.

664401823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1854.

The product of its (nonzero) digits is 27648, while the sum is 34.

The square root of 664401823 is about 25775.9931525441. The cubic root of 664401823 is about 872.5900807643.

The spelling of 664401823 in words is "six hundred sixty-four million, four hundred one thousand, eight hundred twenty-three".