390391 has 2 divisors, whose sum is σ = 390392. Its totient is φ = 390390.

The previous prime is 390389. The next prime is 390407. The reversal of 390391 is 193093.

It is a weak prime.

It is an emirp because it is prime and its reverse (193093) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 390391 - 2¹ = 390389 is a prime.

Together with 390389, it forms a pair of twin primes.

390391 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (390191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195195 + 195196.

It is an arithmetic number, because the mean of its divisors is an integer number (195196).

2³⁹⁰³⁹¹ is an apocalyptic number.

390391 is a deficient number, since it is larger than the sum of its proper divisors (1).

390391 is an equidigital number, since it uses as much as digits as its factorization.

390391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 729, while the sum is 25.

The square root of 390391 is about 624.8127719565. The cubic root of 390391 is about 73.0858438431.

The spelling of 390391 in words is "three hundred ninety thousand, three hundred ninety-one".