664843289 has 8 divisors (see below), whose sum is σ = 738968832. Its totient is φ = 592998640.

The previous prime is 664843273. The next prime is 664843303. The reversal of 664843289 is 982348466.

It is a happy number.

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 664843289 - 2⁴ = 664843273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664843889) 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 7 ways as a sum of consecutive naturals, for example, 569609 + ... + 570774.

It is an arithmetic number, because the mean of its divisors is an integer number (92371104).

Almost surely, 2^664843289 is an apocalyptic number.

It is an amenable number.

664843289 is a deficient number, since it is larger than the sum of its proper divisors (74125543).

664843289 is a wasteful number, since it uses less digits than its factorization.

664843289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1140447.

The product of its digits is 1990656, while the sum is 50.

The square root of 664843289 is about 25784.5552414619. Note that the first 3 decimals coincide. The cubic root of 664843289 is about 872.7833039767.

The spelling of 664843289 in words is "six hundred sixty-four million, eight hundred forty-three thousand, two hundred eighty-nine".