165530523 has 4 divisors (see below), whose sum is σ = 220707368. Its totient is φ = 110353680.

The previous prime is 165530509. The next prime is 165530537. The reversal of 165530523 is 325035561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 325035561 = 3 ⋅108345187.

It is an interprime number because it is at equal distance from previous prime (165530509) and next prime (165530537).

It is not a de Polignac number, because 165530523 - 2¹⁰ = 165529499 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165530623) 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, 27588418 + ... + 27588423.

It is an arithmetic number, because the mean of its divisors is an integer number (55176842).

Almost surely, 2^165530523 is an apocalyptic number.

165530523 is a deficient number, since it is larger than the sum of its proper divisors (55176845).

165530523 is an equidigital number, since it uses as much as digits as its factorization.

165530523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55176844.

The product of its (nonzero) digits is 13500, while the sum is 30.

The square root of 165530523 is about 12865.8665856599. The cubic root of 165530523 is about 549.0678679605.

The spelling of 165530523 in words is "one hundred sixty-five million, five hundred thirty thousand, five hundred twenty-three".