664617 has 4 divisors (see below), whose sum is σ = 886160. Its totient is φ = 443076.

The previous prime is 664613. The next prime is 664619. The reversal of 664617 is 716466.

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 not a de Polignac number, because 664617 - 2² = 664613 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664613) 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 3 ways as a sum of consecutive naturals, for example, 110767 + ... + 110772.

It is an arithmetic number, because the mean of its divisors is an integer number (221540).

2⁶⁶⁴⁶¹⁷ is an apocalyptic number.

It is an amenable number.

664617 is a deficient number, since it is larger than the sum of its proper divisors (221543).

664617 is a wasteful number, since it uses less digits than its factorization.

664617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221542.

The product of its digits is 6048, while the sum is 30.

The square root of 664617 is about 815.2404553259. The cubic root of 664617 is about 87.2684271279.

The spelling of 664617 in words is "six hundred sixty-four thousand, six hundred seventeen".