664123885 has 8 divisors (see below), whose sum is σ = 797091480. Its totient is φ = 531203904.

The previous prime is 664123829. The next prime is 664123909. The reversal of 664123885 is 588321466.

It can be written as a sum of positive squares in 4 ways, for example, as 1885129 + 662238756 = 1373^2 + 25734^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 664123885 - 2⁹ = 664123373 is a prime.

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 7 ways as a sum of consecutive naturals, for example, 37231 + ... + 52099.

It is an arithmetic number, because the mean of its divisors is an integer number (99636435).

Almost surely, 2^664123885 is an apocalyptic number.

It is an amenable number.

664123885 is a deficient number, since it is larger than the sum of its proper divisors (132967595).

664123885 is a wasteful number, since it uses less digits than its factorization.

664123885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23807.

The product of its digits is 276480, while the sum is 43.

The square root of 664123885 is about 25770.6011765345. The cubic root of 664123885 is about 872.4683874557.

The spelling of 664123885 in words is "six hundred sixty-four million, one hundred twenty-three thousand, eight hundred eighty-five".