664203645 has 40 divisors (see below), whose sum is σ = 1360744704. Its totient is φ = 303634656.

The previous prime is 664203643. The next prime is 664203679. The reversal of 664203645 is 546302466.

664203645 is a `hidden beast` number, since 6 + 6 + 4 + 2 + 0 + 3 + 645 = 666.

It is not a de Polignac number, because 664203645 - 2¹ = 664203643 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664203641) by changing a digit.

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 39 ways as a sum of consecutive naturals, for example, 114309 + ... + 119978.

Almost surely, 2^664203645 is an apocalyptic number.

It is an amenable number.

664203645 is an abundant number, since it is smaller than the sum of its proper divisors (696541059).

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

664203645 is a wasteful number, since it uses less digits than its factorization.

664203645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234311 (or 234302 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 36.

The square root of 664203645 is about 25772.1486298679. The cubic root of 664203645 is about 872.5033133154.

The spelling of 664203645 in words is "six hundred sixty-four million, two hundred three thousand, six hundred forty-five".