664446 has 32 divisors (see below), whose sum is σ = 1417248. Its totient is φ = 207360.

The previous prime is 664441. The next prime is 664459. The reversal of 664446 is 644466.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is a congruent number.

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

664446 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 15 ways as a sum of consecutive naturals, for example, 9066 + ... + 9138.

It is an arithmetic number, because the mean of its divisors is an integer number (44289).

2⁶⁶⁴⁴⁴⁶ is an apocalyptic number.

664446 is an abundant number, since it is smaller than the sum of its proper divisors (752802).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

664446 is a wasteful number, since it uses less digits than its factorization.

664446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156.

The product of its digits is 13824, while the sum is 30.

The square root of 664446 is about 815.1355715462. The cubic root of 664446 is about 87.2609420244.

The spelling of 664446 in words is "six hundred sixty-four thousand, four hundred forty-six".