165648961 has 4 divisors (see below), whose sum is σ = 165679492. Its totient is φ = 165618432.

The previous prime is 165648953. The next prime is 165648971. The reversal of 165648961 is 169846561.

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

It can be written as a sum of positive squares in 2 ways, for example, as 164968336 + 680625 = 12844^2 + 825^2 .

It is a cyclic number.

It is not a de Polignac number, because 165648961 - 2³ = 165648953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165648971) 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, 4680 + ... + 18793.

It is an arithmetic number, because the mean of its divisors is an integer number (41419873).

Almost surely, 2^165648961 is an apocalyptic number.

It is an amenable number.

165648961 is a deficient number, since it is larger than the sum of its proper divisors (30531).

165648961 is an equidigital number, since it uses as much as digits as its factorization.

165648961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30530.

The product of its digits is 311040, while the sum is 46.

The square root of 165648961 is about 12870.4685617890. The cubic root of 165648961 is about 549.1987904338.

The spelling of 165648961 in words is "one hundred sixty-five million, six hundred forty-eight thousand, nine hundred sixty-one".