391778668364 has 12 divisors (see below), whose sum is σ = 690214098000. Its totient is φ = 194574640368.

The previous prime is 391778668363. The next prime is 391778668387. The reversal of 391778668364 is 463866877193.

It is a hoax number, since the sum of its digits (68) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 391778668294 and 391778668303.

It is not an unprimeable number, because it can be changed into a prime (391778668361) 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, 328672784 + ... + 328673975.

It is an arithmetic number, because the mean of its divisors is an integer number (57517841500).

Almost surely, 2^391778668364 is an apocalyptic number.

It is an amenable number.

391778668364 is a deficient number, since it is larger than the sum of its proper divisors (298435429636).

391778668364 is a wasteful number, since it uses less digits than its factorization.

391778668364 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 657346912 (or 657346910 counting only the distinct ones).

The product of its digits is 219469824, while the sum is 68.

The spelling of 391778668364 in words is "three hundred ninety-one billion, seven hundred seventy-eight million, six hundred sixty-eight thousand, three hundred sixty-four".