165848561 has 4 divisors (see below), whose sum is σ = 173059392. Its totient is φ = 158637732.

The previous prime is 165848539. The next prime is 165848581.

165848561 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 165848561 - 2⁶ = 165848497 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (165848521) 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, 3605381 + ... + 3605426.

It is an arithmetic number, because the mean of its divisors is an integer number (43264848).

Almost surely, 2^165848561 is an apocalyptic number.

It is an amenable number.

165848561 is a deficient number, since it is larger than the sum of its proper divisors (7210831).

165848561 is an equidigital number, since it uses as much as digits as its factorization.

165848561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7210830.

The product of its digits is 230400, while the sum is 44.

The square root of 165848561 is about 12878.2204127744. The cubic root of 165848561 is about 549.4192890073.

The spelling of 165848561 in words is "one hundred sixty-five million, eight hundred forty-eight thousand, five hundred sixty-one".