320565155 has 4 divisors (see below), whose sum is σ = 384678192. Its totient is φ = 256452120.

The previous prime is 320565143. The next prime is 320565199. The reversal of 320565155 is 551565023.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 551565023 = 3593 ⋅153511.

It is not a de Polignac number, because 320565155 - 2⁸ = 320564899 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 32056511 + ... + 32056520.

It is an arithmetic number, because the mean of its divisors is an integer number (96169548).

Almost surely, 2^320565155 is an apocalyptic number.

320565155 is a deficient number, since it is larger than the sum of its proper divisors (64113037).

320565155 is an equidigital number, since it uses as much as digits as its factorization.

320565155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64113036.

The product of its (nonzero) digits is 22500, while the sum is 32.

The square root of 320565155 is about 17904.3334140090. Note that the first 3 decimals coincide. The cubic root of 320565155 is about 684.3928091249.

The spelling of 320565155 in words is "three hundred twenty million, five hundred sixty-five thousand, one hundred fifty-five".