391679999999 has 4 divisors (see below), whose sum is σ = 391698528936. Its totient is φ = 391661471064.

The previous prime is 391679999993. The next prime is 391680000007. The reversal of 391679999999 is 999999976193.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 999999976193 = 67 ⋅14925372779.

It is a cyclic number.

It is not a de Polignac number, because 391679999999 - 2³² = 387385032703 is a prime.

It is a Duffinian number.

391679999999 is a modest number, since divided by 999999 gives 391679 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391679999993) 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, 9232724 + ... + 9275049.

It is an arithmetic number, because the mean of its divisors is an integer number (97924632234).

Almost surely, 2^391679999999 is an apocalyptic number.

391679999999 is a deficient number, since it is larger than the sum of its proper divisors (18528937).

391679999999 is a wasteful number, since it uses less digits than its factorization.

391679999999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18528936.

The product of its digits is 5423886846, while the sum is 89.

The spelling of 391679999999 in words is "three hundred ninety-one billion, six hundred seventy-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".