391191 has 8 divisors (see below), whose sum is σ = 549120. Its totient is φ = 247032.

The previous prime is 391177. The next prime is 391199. The reversal of 391191 is 191193.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 391191 - 2⁵ = 391159 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3375 + ... + 3488.

It is an arithmetic number, because the mean of its divisors is an integer number (68640).

2³⁹¹¹⁹¹ is an apocalyptic number.

391191 is a deficient number, since it is larger than the sum of its proper divisors (157929).

391191 is a wasteful number, since it uses less digits than its factorization.

391191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6885.

The product of its digits is 243, while the sum is 24.

The square root of 391191 is about 625.4526360965. The cubic root of 391191 is about 73.1357329560.

The spelling of 391191 in words is "three hundred ninety-one thousand, one hundred ninety-one".