664493 has 8 divisors (see below), whose sum is σ = 701568. Its totient is φ = 628144.

The previous prime is 664471. The next prime is 664507. The reversal of 664493 is 394466.

664493 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664493 is a prime.

It is a Duffinian number.

It is a plaindrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664403) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3755 + ... + 3927.

It is an arithmetic number, because the mean of its divisors is an integer number (87696).

2⁶⁶⁴⁴⁹³ is an apocalyptic number.

It is an amenable number.

664493 is a deficient number, since it is larger than the sum of its proper divisors (37075).

664493 is a wasteful number, since it uses less digits than its factorization.

664493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363.

The product of its digits is 15552, while the sum is 32.

The square root of 664493 is about 815.1644005966. The cubic root of 664493 is about 87.2629994616.

The spelling of 664493 in words is "six hundred sixty-four thousand, four hundred ninety-three".