668438 has 8 divisors (see below), whose sum is σ = 1019280. Its totient is φ = 328680.

The previous prime is 668417. The next prime is 668471. The reversal of 668438 is 834866.

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

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 668398 and 668407.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2618 + ... + 2861.

It is an arithmetic number, because the mean of its divisors is an integer number (127410).

2⁶⁶⁸⁴³⁸ is an apocalyptic number.

668438 is a deficient number, since it is larger than the sum of its proper divisors (350842).

668438 is a wasteful number, since it uses less digits than its factorization.

668438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5542.

The product of its digits is 27648, while the sum is 35.

The square root of 668438 is about 817.5805770687. The cubic root of 668438 is about 87.4353481603.

The spelling of 668438 in words is "six hundred sixty-eight thousand, four hundred thirty-eight".