668455 has 4 divisors (see below), whose sum is σ = 802152. Its totient is φ = 534760.

The previous prime is 668417. The next prime is 668471. The reversal of 668455 is 554866.

668455 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 is not a de Polignac number, because 668455 - 2¹⁹ = 144167 is a prime.

It is a Duffinian number.

668455 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 668455.

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, 66841 + ... + 66850.

It is an arithmetic number, because the mean of its divisors is an integer number (200538).

2⁶⁶⁸⁴⁵⁵ is an apocalyptic number.

668455 is a deficient number, since it is larger than the sum of its proper divisors (133697).

668455 is a wasteful number, since it uses less digits than its factorization.

668455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133696.

The product of its digits is 28800, while the sum is 34.

The square root of 668455 is about 817.5909735314. The cubic root of 668455 is about 87.4360893850.

The spelling of 668455 in words is "six hundred sixty-eight thousand, four hundred fifty-five".