668459383954865 has 16 divisors (see below), whose sum is σ = 811310523380352. Its totient is φ = 528681857036544.

The previous prime is 668459383954861. The next prime is 668459383954919. The reversal of 668459383954865 is 568459383954866.

It is a cyclic number.

It is not a de Polignac number, because 668459383954865 - 2² = 668459383954861 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (668459383954861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1282549304 + ... + 1283070393.

It is an arithmetic number, because the mean of its divisors is an integer number (50706907711272).

Almost surely, 2^{668459383954865} is an apocalyptic number.

It is an amenable number.

668459383954865 is a deficient number, since it is larger than the sum of its proper divisors (142851139425487).

668459383954865 is a wasteful number, since it uses less digits than its factorization.

668459383954865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2565620296.

The product of its digits is 161243136000, while the sum is 89.

Subtracting from 668459383954865 its reverse (568459383954866), we obtain a palindrome (99999999999999).

The spelling of 668459383954865 in words is "six hundred sixty-eight trillion, four hundred fifty-nine billion, three hundred eighty-three million, nine hundred fifty-four thousand, eight hundred sixty-five".