668686867 has 8 divisors (see below), whose sum is σ = 681523200. Its totient is φ = 655934664.

The previous prime is 668686859. The next prime is 668686873. The reversal of 668686867 is 768686866.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 668686867 - 2³ = 668686859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (668686807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4867 + ... + 36892.

It is an arithmetic number, because the mean of its divisors is an integer number (85190400).

Almost surely, 2^668686867 is an apocalyptic number.

668686867 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

668686867 is a deficient number, since it is larger than the sum of its proper divisors (12836333).

668686867 is a wasteful number, since it uses less digits than its factorization.

668686867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42065.

The product of its digits is 27869184, while the sum is 61.

The square root of 668686867 is about 25858.9803936659. The cubic root of 668686867 is about 874.4619786906.

Subtracting 668686867 from its reverse (768686866), we obtain a palindrome (99999999).

The spelling of 668686867 in words is "six hundred sixty-eight million, six hundred eighty-six thousand, eight hundred sixty-seven".