668858 has 4 divisors (see below), whose sum is σ = 1003290. Its totient is φ = 334428.

The previous prime is 668851. The next prime is 668867. The reversal of 668858 is 858866.

668858 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 667489 + 1369 = 817^2 + 37^2 .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 668858.

It is not an unprimeable number, because it can be changed into a prime (668851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 167213 + ... + 167216.

2⁶⁶⁸⁸⁵⁸ is an apocalyptic number.

668858 is a deficient number, since it is larger than the sum of its proper divisors (334432).

668858 is a wasteful number, since it uses less digits than its factorization.

668858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334431.

The product of its digits is 92160, while the sum is 41.

The square root of 668858 is about 817.8373921508. The cubic root of 668858 is about 87.4536570922.

The spelling of 668858 in words is "six hundred sixty-eight thousand, eight hundred fifty-eight".