666320564 has 48 divisors (see below), whose sum is σ = 1437410688. Its totient is φ = 263184768.

The previous prime is 666320521. The next prime is 666320573. The reversal of 666320564 is 465023666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 343742 + ... + 345674.

It is an arithmetic number, because the mean of its divisors is an integer number (29946056).

Almost surely, 2^666320564 is an apocalyptic number.

It is an amenable number.

666320564 is an abundant number, since it is smaller than the sum of its proper divisors (771090124).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

666320564 is a wasteful number, since it uses less digits than its factorization.

666320564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2904 (or 2902 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 38.

The square root of 666320564 is about 25813.1858552950. The cubic root of 666320564 is about 873.4292643036.

The spelling of 666320564 in words is "six hundred sixty-six million, three hundred twenty thousand, five hundred sixty-four".