664465679 has 4 divisors (see below), whose sum is σ = 667223040. Its totient is φ = 661708320.

The previous prime is 664465657. The next prime is 664465691. The reversal of 664465679 is 976564466.

It is a happy number.

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 664465679 - 2²⁰ = 663417103 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 664465679.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664465079) 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, 1378319 + ... + 1378800.

It is an arithmetic number, because the mean of its divisors is an integer number (166805760).

Almost surely, 2^664465679 is an apocalyptic number.

664465679 is a deficient number, since it is larger than the sum of its proper divisors (2757361).

664465679 is a wasteful number, since it uses less digits than its factorization.

664465679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2757360.

The product of its digits is 6531840, while the sum is 53.

The square root of 664465679 is about 25777.2317947448. The cubic root of 664465679 is about 872.6180348955.

The spelling of 664465679 in words is "six hundred sixty-four million, four hundred sixty-five thousand, six hundred seventy-nine".