668358015838 has 4 divisors (see below), whose sum is σ = 1002537023760. Its totient is φ = 334179007918.

The previous prime is 668358015827. The next prime is 668358015839. The reversal of 668358015838 is 838510853866.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668358015839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 167089503958 + ... + 167089503961.

It is an arithmetic number, because the mean of its divisors is an integer number (250634255940).

Almost surely, 2^668358015838 is an apocalyptic number.

668358015838 is a deficient number, since it is larger than the sum of its proper divisors (334179007922).

668358015838 is a wasteful number, since it uses less digits than its factorization.

668358015838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334179007921.

The product of its (nonzero) digits is 33177600, while the sum is 61.

The spelling of 668358015838 in words is "six hundred sixty-eight billion, three hundred fifty-eight million, fifteen thousand, eight hundred thirty-eight".