668208523 has 4 divisors (see below), whose sum is σ = 668312488. Its totient is φ = 668104560.

The previous prime is 668208461. The next prime is 668208533. The reversal of 668208523 is 325802866.

668208523 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 a cyclic number.

It is not a de Polignac number, because 668208523 - 2⁹ = 668208011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (668208533) 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, 41658 + ... + 55423.

It is an arithmetic number, because the mean of its divisors is an integer number (167078122).

Almost surely, 2^668208523 is an apocalyptic number.

668208523 is a deficient number, since it is larger than the sum of its proper divisors (103965).

668208523 is an equidigital number, since it uses as much as digits as its factorization.

668208523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103964.

The product of its (nonzero) digits is 138240, while the sum is 40.

The square root of 668208523 is about 25849.7296504238. The cubic root of 668208523 is about 874.2534139932.

The spelling of 668208523 in words is "six hundred sixty-eight million, two hundred eight thousand, five hundred twenty-three".