391693686839 has 48 divisors (see below), whose sum is σ = 498270382848. Its totient is φ = 305140566528.

The previous prime is 391693686833. The next prime is 391693686847. The reversal of 391693686839 is 938686396193.

It is not a de Polignac number, because 391693686839 - 2⁴ = 391693686823 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391693686833) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 28219169 + ... + 28233045.

It is an arithmetic number, because the mean of its divisors is an integer number (10380632976).

Almost surely, 2^391693686839 is an apocalyptic number.

391693686839 is a deficient number, since it is larger than the sum of its proper divisors (106576696009).

391693686839 is a wasteful number, since it uses less digits than its factorization.

391693686839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14584 (or 14577 counting only the distinct ones).

The product of its digits is 272097792, while the sum is 71.

The spelling of 391693686839 in words is "three hundred ninety-one billion, six hundred ninety-three million, six hundred eighty-six thousand, eight hundred thirty-nine".