664040523 has 4 divisors (see below), whose sum is σ = 885387368. Its totient is φ = 442693680.

The previous prime is 664040497. The next prime is 664040527. The reversal of 664040523 is 325040466.

664040523 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 664040523 - 2⁹ = 664040011 is a prime.

It is a super-2 number, since 2×664040523² = 881899632372227058, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664040527) 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, 110673418 + ... + 110673423.

It is an arithmetic number, because the mean of its divisors is an integer number (221346842).

Almost surely, 2^664040523 is an apocalyptic number.

664040523 is a deficient number, since it is larger than the sum of its proper divisors (221346845).

664040523 is a wasteful number, since it uses less digits than its factorization.

664040523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221346844.

The product of its (nonzero) digits is 17280, while the sum is 30.

The square root of 664040523 is about 25768.9837401478. The cubic root of 664040523 is about 872.4318813386.

Adding to 664040523 its reverse (325040466), we get a palindrome (989080989).

The spelling of 664040523 in words is "six hundred sixty-four million, forty thousand, five hundred twenty-three".