664567423 has 4 divisors (see below), whose sum is σ = 715688008. Its totient is φ = 613446840.

The previous prime is 664567411. The next prime is 664567447. The reversal of 664567423 is 324765466.

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 664567423 - 2⁹ = 664566911 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 664567423.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664567823) 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, 25560273 + ... + 25560298.

It is an arithmetic number, because the mean of its divisors is an integer number (178922002).

Almost surely, 2^664567423 is an apocalyptic number.

664567423 is a deficient number, since it is larger than the sum of its proper divisors (51120585).

664567423 is a wasteful number, since it uses less digits than its factorization.

664567423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51120584.

The product of its digits is 725760, while the sum is 43.

The square root of 664567423 is about 25779.2052437619. The cubic root of 664567423 is about 872.6625714913.

The spelling of 664567423 in words is "six hundred sixty-four million, five hundred sixty-seven thousand, four hundred twenty-three".