664992576 has 84 divisors (see below), whose sum is σ = 1910372100. Its totient is φ = 221165568.

The previous prime is 664992557. The next prime is 664992709. The reversal of 664992576 is 675299466.

664992576 is a `hidden beast` number, since 6 + 64 + 9 + 9 + 2 + 576 = 666.

664992576 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 439992576 + 225000000 = 20976^2 + 15000^2 .

It is a super-2 number, since 2×664992576² = 884430252270231552, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 326730 + ... + 328758.

It is an arithmetic number, because the mean of its divisors is an integer number (22742525).

Almost surely, 2^664992576 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664992576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (955186050).

664992576 is an abundant number, since it is smaller than the sum of its proper divisors (1245379524).

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

664992576 is a wasteful number, since it uses less digits than its factorization.

664992576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2616 (or 2603 counting only the distinct ones).

The product of its digits is 4898880, while the sum is 54.

The square root of 664992576 is about 25787.4499708676. The cubic root of 664992576 is about 872.8486253600.

It can be divided in two parts, 6649 and 92576, that added together give a square (99225 = 315²).

The spelling of 664992576 in words is "six hundred sixty-four million, nine hundred ninety-two thousand, five hundred seventy-six".