668051256794 has 4 divisors (see below), whose sum is σ = 1002076885194. Its totient is φ = 334025628396.

The previous prime is 668051256793. The next prime is 668051256799. The reversal of 668051256794 is 497652150866.

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

It can be written as a sum of positive squares in only one way, i.e., 574162330225 + 93888926569 = 757735^2 + 306413^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (668051256793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 167012814197 + ... + 167012814200.

Almost surely, 2^668051256794 is an apocalyptic number.

668051256794 is a deficient number, since it is larger than the sum of its proper divisors (334025628400).

668051256794 is a wasteful number, since it uses less digits than its factorization.

668051256794 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334025628399.

The product of its (nonzero) digits is 21772800, while the sum is 59.

The spelling of 668051256794 in words is "six hundred sixty-eight billion, fifty-one million, two hundred fifty-six thousand, seven hundred ninety-four".