668678 has 16 divisors (see below), whose sum is σ = 1080864. Its totient is φ = 309120.

The previous prime is 668677. The next prime is 668687. The reversal of 668678 is 876866.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668671) 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 7 ways as a sum of consecutive naturals, for example, 2276 + ... + 2552.

It is an arithmetic number, because the mean of its divisors is an integer number (67554).

2⁶⁶⁸⁶⁷⁸ is an apocalyptic number.

668678 is a deficient number, since it is larger than the sum of its proper divisors (412186).

668678 is a wasteful number, since it uses less digits than its factorization.

668678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 367.

The product of its digits is 96768, while the sum is 41.

The square root of 668678 is about 817.7273384203. The cubic root of 668678 is about 87.4458113459.

The spelling of 668678 in words is "six hundred sixty-eight thousand, six hundred seventy-eight".