664742329 has 4 divisors (see below), whose sum is σ = 666553984. Its totient is φ = 662930676.

The previous prime is 664742249. The next prime is 664742359. The reversal of 664742329 is 923247466.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 664742329 - 2⁹ = 664741817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664742359) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 905277 + ... + 906010.

It is an arithmetic number, because the mean of its divisors is an integer number (166638496).

Almost surely, 2^664742329 is an apocalyptic number.

It is an amenable number.

664742329 is a deficient number, since it is larger than the sum of its proper divisors (1811655).

664742329 is a wasteful number, since it uses less digits than its factorization.

664742329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1811654.

The product of its digits is 435456, while the sum is 43.

The square root of 664742329 is about 25782.5974060024. The cubic root of 664742329 is about 872.7391228067.

The spelling of 664742329 in words is "six hundred sixty-four million, seven hundred forty-two thousand, three hundred twenty-nine".