668589 has 4 divisors (see below), whose sum is σ = 891456. Its totient is φ = 445724.

The previous prime is 668581. The next prime is 668599. The reversal of 668589 is 985866.

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 a cyclic number.

It is not a de Polignac number, because 668589 - 2³ = 668581 is a prime.

It is a super-2 number, since 2×668589² = 894022501842, which contains 22 as substring.

It is a D-number.

It is a self number, because there is not a number n which added to its sum of digits gives 668589.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668581) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 111429 + ... + 111434.

It is an arithmetic number, because the mean of its divisors is an integer number (222864).

2⁶⁶⁸⁵⁸⁹ is an apocalyptic number.

It is an amenable number.

668589 is a deficient number, since it is larger than the sum of its proper divisors (222867).

668589 is a wasteful number, since it uses less digits than its factorization.

668589 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222866.

The product of its digits is 103680, while the sum is 42.

The square root of 668589 is about 817.6729174921. The cubic root of 668589 is about 87.4419315400.

The spelling of 668589 in words is "six hundred sixty-eight thousand, five hundred eighty-nine".