664106879 has 4 divisors (see below), whose sum is σ = 664246176. Its totient is φ = 663967584.

The previous prime is 664106827. The next prime is 664106903. The reversal of 664106879 is 978601466.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664106879 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 (664106279) 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, 62234 + ... + 72119.

It is an arithmetic number, because the mean of its divisors is an integer number (166061544).

Almost surely, 2^664106879 is an apocalyptic number.

664106879 is a deficient number, since it is larger than the sum of its proper divisors (139297).

664106879 is a wasteful number, since it uses less digits than its factorization.

664106879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139296.

The product of its (nonzero) digits is 435456, while the sum is 47.

The square root of 664106879 is about 25770.2712248048. The cubic root of 664106879 is about 872.4609403893.

The spelling of 664106879 in words is "six hundred sixty-four million, one hundred six thousand, eight hundred seventy-nine".