664767818 has 32 divisors (see below), whose sum is σ = 1174061952. Its totient is φ = 278308800.

The previous prime is 664767799. The next prime is 664767823. The reversal of 664767818 is 818767466.

It is a super-2 number, since 2×664767818² = 883832503696962248, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 664767818.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 141548 + ... + 146168.

It is an arithmetic number, because the mean of its divisors is an integer number (36689436).

Almost surely, 2^664767818 is an apocalyptic number.

664767818 is a deficient number, since it is larger than the sum of its proper divisors (509294134).

664767818 is a wasteful number, since it uses less digits than its factorization.

664767818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5150.

The product of its digits is 2709504, while the sum is 53.

The square root of 664767818 is about 25783.0917075513. The cubic root of 664767818 is about 872.7502774864.

The spelling of 664767818 in words is "six hundred sixty-four million, seven hundred sixty-seven thousand, eight hundred eighteen".