664388992 has 32 divisors (see below), whose sum is σ = 1351761120. Its totient is φ = 325123584.

The previous prime is 664388957. The next prime is 664388999. The reversal of 664388992 is 299883466.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664388999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49203 + ... + 61234.

It is an arithmetic number, because the mean of its divisors is an integer number (42242535).

Almost surely, 2^664388992 is an apocalyptic number.

It is an amenable number.

664388992 is an abundant number, since it is smaller than the sum of its proper divisors (687372128).

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

664388992 is a wasteful number, since it uses less digits than its factorization.

664388992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110498 (or 110486 counting only the distinct ones).

The product of its digits is 4478976, while the sum is 55.

The square root of 664388992 is about 25775.7442569560. The cubic root of 664388992 is about 872.5844635434.

The spelling of 664388992 in words is "six hundred sixty-four million, three hundred eighty-eight thousand, nine hundred ninety-two".