668493 has 28 divisors (see below), whose sum is σ = 1154208. Its totient is φ = 379080.

The previous prime is 668471. The next prime is 668509. The reversal of 668493 is 394866.

668493 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 668493 - 2¹⁸ = 406349 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668093) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 5038 + ... + 5168.

2⁶⁶⁸⁴⁹³ is an apocalyptic number.

668493 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

It is an amenable number.

668493 is a deficient number, since it is larger than the sum of its proper divisors (485715).

668493 is an equidigital number, since it uses as much as digits as its factorization.

668493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 141 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 668493 is about 817.6142122052. The cubic root of 668493 is about 87.4377461949.

The spelling of 668493 in words is "six hundred sixty-eight thousand, four hundred ninety-three".