668606 has 8 divisors (see below), whose sum is σ = 1012440. Its totient is φ = 331128.

The previous prime is 668599. The next prime is 668609. The reversal of 668606 is 606866.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668609) by changing a digit.

668606 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 3 ways as a sum of consecutive naturals, for example, 1316 + ... + 1751.

It is an arithmetic number, because the mean of its divisors is an integer number (126555).

2⁶⁶⁸⁶⁰⁶ is an apocalyptic number.

668606 is a deficient number, since it is larger than the sum of its proper divisors (343834).

668606 is a wasteful number, since it uses less digits than its factorization.

668606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3178.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 668606 is about 817.6833127807. The cubic root of 668606 is about 87.4426726531.

It can be divided in two parts, 66860 and 6, that added together give a palindrome (66866).

The spelling of 668606 in words is "six hundred sixty-eight thousand, six hundred six".