668393 has 4 divisors (see below), whose sum is σ = 729168. Its totient is φ = 607620.

The previous prime is 668347. The next prime is 668407. The reversal of 668393 is 393866.

668393 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, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (668303) 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, 30371 + ... + 30392.

It is an arithmetic number, because the mean of its divisors is an integer number (182292).

2⁶⁶⁸³⁹³ is an apocalyptic number.

It is an amenable number.

668393 is a deficient number, since it is larger than the sum of its proper divisors (60775).

668393 is a wasteful number, since it uses less digits than its factorization.

668393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60774.

The product of its digits is 23328, while the sum is 35.

The square root of 668393 is about 817.5530563823. The cubic root of 668393 is about 87.4333860342.

It can be divided in two parts, 6683 and 93, that added together give a palindrome (6776).

The spelling of 668393 in words is "six hundred sixty-eight thousand, three hundred ninety-three".