320560391 has 4 divisors (see below), whose sum is σ = 321198192. Its totient is φ = 319922592.

The previous prime is 320560363. The next prime is 320560421. The reversal of 320560391 is 193065023.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 320560391 - 2⁶ = 320560327 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 (320560091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 318146 + ... + 319151.

It is an arithmetic number, because the mean of its divisors is an integer number (80299548).

Almost surely, 2^320560391 is an apocalyptic number.

320560391 is a deficient number, since it is larger than the sum of its proper divisors (637801).

320560391 is an equidigital number, since it uses as much as digits as its factorization.

320560391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637800.

The product of its (nonzero) digits is 4860, while the sum is 29.

The square root of 320560391 is about 17904.2003730968. The cubic root of 320560391 is about 684.3894187965.

The spelling of 320560391 in words is "three hundred twenty million, five hundred sixty thousand, three hundred ninety-one".