664449 has 8 divisors (see below), whose sum is σ = 932640. Its totient is φ = 419616.

The previous prime is 664441. The next prime is 664459. The reversal of 664449 is 944466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 664449 - 2³ = 664441 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

664449 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (664441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5772 + ... + 5885.

It is an arithmetic number, because the mean of its divisors is an integer number (116580).

2⁶⁶⁴⁴⁴⁹ is an apocalyptic number.

It is an amenable number.

664449 is a deficient number, since it is larger than the sum of its proper divisors (268191).

664449 is a wasteful number, since it uses less digits than its factorization.

664449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11679.

The product of its digits is 20736, while the sum is 33.

The square root of 664449 is about 815.1374117288. The cubic root of 664449 is about 87.2610733531.

The spelling of 664449 in words is "six hundred sixty-four thousand, four hundred forty-nine".