391387 has 2 divisors, whose sum is σ = 391388. Its totient is φ = 391386.

The previous prime is 391379. The next prime is 391393. The reversal of 391387 is 783193.

It is a strong prime.

It is an emirp because it is prime and its reverse (783193) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 391387 - 2³ = 391379 is a prime.

It is not a weakly prime, because it can be changed into another prime (391337) 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 as a sum of consecutive naturals, namely, 195693 + 195694.

It is an arithmetic number, because the mean of its divisors is an integer number (195694).

2³⁹¹³⁸⁷ is an apocalyptic number.

391387 is a deficient number, since it is larger than the sum of its proper divisors (1).

391387 is an equidigital number, since it uses as much as digits as its factorization.

391387 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536, while the sum is 31.

The square root of 391387 is about 625.6093029999. The cubic root of 391387 is about 73.1479454134.

The spelling of 391387 in words is "three hundred ninety-one thousand, three hundred eighty-seven".