165530813 has 16 divisors (see below), whose sum is σ = 193013760. Its totient is φ = 139023216.

The previous prime is 165530797. The next prime is 165530821. The reversal of 165530813 is 318035561.

It is a cyclic number.

It is not a de Polignac number, because 165530813 - 2⁴ = 165530797 is a prime.

It is a super-3 number, since 3×165530813³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 165530813.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165530863) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 200720 + ... + 201542.

It is an arithmetic number, because the mean of its divisors is an integer number (12063360).

Almost surely, 2^165530813 is an apocalyptic number.

It is an amenable number.

165530813 is a deficient number, since it is larger than the sum of its proper divisors (27482947).

165530813 is an equidigital number, since it uses as much as digits as its factorization.

165530813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1376.

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 165530813 is about 12865.8778557858. The cubic root of 165530813 is about 549.0681886055.

The spelling of 165530813 in words is "one hundred sixty-five million, five hundred thirty thousand, eight hundred thirteen".