664345579 has 4 divisors (see below), whose sum is σ = 670923360. Its totient is φ = 657767800.

The previous prime is 664345553. The next prime is 664345631. The reversal of 664345579 is 975543466.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664345579 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664345379) 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, 3288739 + ... + 3288940.

It is an arithmetic number, because the mean of its divisors is an integer number (167730840).

Almost surely, 2^664345579 is an apocalyptic number.

664345579 is a deficient number, since it is larger than the sum of its proper divisors (6577781).

664345579 is a wasteful number, since it uses less digits than its factorization.

664345579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6577780.

The product of its digits is 2721600, while the sum is 49.

The square root of 664345579 is about 25774.9021142661. The cubic root of 664345579 is about 872.5654574416.

The spelling of 664345579 in words is "six hundred sixty-four million, three hundred forty-five thousand, five hundred seventy-nine".