668956 has 12 divisors (see below), whose sum is σ = 1199520. Its totient is φ = 326240.

The previous prime is 668947. The next prime is 668959. The reversal of 668956 is 659866.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668959) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1876 + ... + 2203.

It is an arithmetic number, because the mean of its divisors is an integer number (99960).

2⁶⁶⁸⁹⁵⁶ is an apocalyptic number.

It is an amenable number.

668956 is a deficient number, since it is larger than the sum of its proper divisors (530564).

668956 is a wasteful number, since it uses less digits than its factorization.

668956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4124 (or 4122 counting only the distinct ones).

The product of its digits is 77760, while the sum is 40.

The square root of 668956 is about 817.8973040670. The cubic root of 668956 is about 87.4579280735.

The spelling of 668956 in words is "six hundred sixty-eight thousand, nine hundred fifty-six".