668378216751 has 16 divisors (see below), whose sum is σ = 1018761704448. Its totient is φ = 381825180000.

The previous prime is 668378216711. The next prime is 668378216797. The reversal of 668378216751 is 157612873866.

It is not a de Polignac number, because 668378216751 - 2⁹ = 668378216239 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668378216711) 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 in 15 ways as a sum of consecutive naturals, for example, 4306500 + ... + 4459001.

It is an arithmetic number, because the mean of its divisors is an integer number (63672606528).

Almost surely, 2^668378216751 is an apocalyptic number.

668378216751 is a deficient number, since it is larger than the sum of its proper divisors (350383487697).

668378216751 is a wasteful number, since it uses less digits than its factorization.

668378216751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8769142.

The product of its digits is 20321280, while the sum is 60.

The spelling of 668378216751 in words is "six hundred sixty-eight billion, three hundred seventy-eight million, two hundred sixteen thousand, seven hundred fifty-one".