391279 has 4 divisors (see below), whose sum is σ = 447184. Its totient is φ = 335376.

The previous prime is 391273. The next prime is 391283. The reversal of 391279 is 972193.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 972193 = 409 ⋅2377.

It is a cyclic number.

It is not a de Polignac number, because 391279 - 2⁵ = 391247 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 391279.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27942 + ... + 27955.

It is an arithmetic number, because the mean of its divisors is an integer number (111796).

2³⁹¹²⁷⁹ is an apocalyptic number.

391279 is a deficient number, since it is larger than the sum of its proper divisors (55905).

391279 is an equidigital number, since it uses as much as digits as its factorization.

391279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55904.

The product of its digits is 3402, while the sum is 31.

The square root of 391279 is about 625.5229811925. The cubic root of 391279 is about 73.1412166046.

The spelling of 391279 in words is "three hundred ninety-one thousand, two hundred seventy-nine".