664670209 has 8 divisors (see below), whose sum is σ = 760192128. Its totient is φ = 569290560.

The previous prime is 664670189. The next prime is 664670249. The reversal of 664670209 is 902076466.

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 664670209 - 2⁷ = 664670081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664670249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25357 + ... + 44410.

It is an arithmetic number, because the mean of its divisors is an integer number (95024016).

Almost surely, 2^664670209 is an apocalyptic number.

It is an amenable number.

664670209 is a deficient number, since it is larger than the sum of its proper divisors (95521919).

664670209 is a wasteful number, since it uses less digits than its factorization.

664670209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71135.

The product of its (nonzero) digits is 108864, while the sum is 40.

The square root of 664670209 is about 25781.1987502521. The cubic root of 664670209 is about 872.7075595883.

The spelling of 664670209 in words is "six hundred sixty-four million, six hundred seventy thousand, two hundred nine".