320523391 has 4 divisors (see below), whose sum is σ = 321031984. Its totient is φ = 320014800.

The previous prime is 320523367. The next prime is 320523397. The reversal of 320523391 is 193325023.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 193325023 = 643 ⋅300661.

It is a cyclic number.

It is not a de Polignac number, because 320523391 - 2⁷ = 320523263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320523397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 253350 + ... + 254611.

It is an arithmetic number, because the mean of its divisors is an integer number (80257996).

Almost surely, 2^320523391 is an apocalyptic number.

320523391 is a deficient number, since it is larger than the sum of its proper divisors (508593).

320523391 is an equidigital number, since it uses as much as digits as its factorization.

320523391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 508592.

The product of its (nonzero) digits is 4860, while the sum is 28.

The square root of 320523391 is about 17903.1670661925. The cubic root of 320523391 is about 684.3630863866.

The spelling of 320523391 in words is "three hundred twenty million, five hundred twenty-three thousand, three hundred ninety-one".