668981154239 has 4 divisors (see below), whose sum is σ = 669556375656. Its totient is φ = 668405932824.

The previous prime is 668981154211. The next prime is 668981154263. The reversal of 668981154239 is 932451189866.

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 668981154239 - 2¹⁶ = 668981088703 is a prime.

It is a super-4 number, since 4×668981154239⁴ (a number of 48 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668981154209) 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, 287608964 + ... + 287611289.

It is an arithmetic number, because the mean of its divisors is an integer number (167389093914).

Almost surely, 2^668981154239 is an apocalyptic number.

668981154239 is a deficient number, since it is larger than the sum of its proper divisors (575221417).

668981154239 is a wasteful number, since it uses less digits than its factorization.

668981154239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 575221416.

The product of its digits is 22394880, while the sum is 62.

The spelling of 668981154239 in words is "six hundred sixty-eight billion, nine hundred eighty-one million, one hundred fifty-four thousand, two hundred thirty-nine".