320765161 has 4 divisors (see below), whose sum is σ = 320828292. Its totient is φ = 320702032.

The previous prime is 320765141. The next prime is 320765171. The reversal of 320765161 is 161567023.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 161567023 = 227 ⋅711749.

It can be written as a sum of positive squares in 2 ways, for example, as 27499536 + 293265625 = 5244^2 + 17125^2 .

It is a cyclic number.

It is not a de Polignac number, because 320765161 - 2⁷ = 320765033 is a prime.

It is a super-2 number, since 2×320765161² = 205780577022711842, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (320765111) 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, 23206 + ... + 34351.

It is an arithmetic number, because the mean of its divisors is an integer number (80207073).

Almost surely, 2^320765161 is an apocalyptic number.

It is an amenable number.

320765161 is a deficient number, since it is larger than the sum of its proper divisors (63131).

320765161 is an equidigital number, since it uses as much as digits as its factorization.

320765161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63130.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 320765161 is about 17909.9179506775. The cubic root of 320765161 is about 684.5351142675.

The spelling of 320765161 in words is "three hundred twenty million, seven hundred sixty-five thousand, one hundred sixty-one".