165729215 has 4 divisors (see below), whose sum is σ = 198875064. Its totient is φ = 132583368.

The previous prime is 165729173. The next prime is 165729217. The reversal of 165729215 is 512927561.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 512927561 = 97 ⋅5287913.

It is a cyclic number.

It is not a de Polignac number, because 165729215 - 2²⁰ = 164680639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165729217) 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, 16572917 + ... + 16572926.

It is an arithmetic number, because the mean of its divisors is an integer number (49718766).

Almost surely, 2^165729215 is an apocalyptic number.

165729215 is a deficient number, since it is larger than the sum of its proper divisors (33145849).

165729215 is an equidigital number, since it uses as much as digits as its factorization.

165729215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33145848.

The product of its digits is 37800, while the sum is 38.

The square root of 165729215 is about 12873.5859417646. The cubic root of 165729215 is about 549.2874684902.

The spelling of 165729215 in words is "one hundred sixty-five million, seven hundred twenty-nine thousand, two hundred fifteen".