668442 has 16 divisors (see below), whose sum is σ = 1373472. Its totient is φ = 216720.

The previous prime is 668417. The next prime is 668471. The reversal of 668442 is 244866.

668442 is nontrivially palindromic in base 7.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 668442.

It is an unprimeable number.

668442 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1284 + ... + 1727.

It is an arithmetic number, because the mean of its divisors is an integer number (85842).

2⁶⁶⁸⁴⁴² is an apocalyptic number.

668442 is an abundant number, since it is smaller than the sum of its proper divisors (705030).

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

668442 is a wasteful number, since it uses less digits than its factorization.

668442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3053.

The product of its digits is 9216, while the sum is 30.

The square root of 668442 is about 817.5830233071. The cubic root of 668442 is about 87.4355225672.

The spelling of 668442 in words is "six hundred sixty-eight thousand, four hundred forty-two".