165434909 has 4 divisors (see below), whose sum is σ = 165466140. Its totient is φ = 165403680.

The previous prime is 165434903. The next prime is 165434911. The reversal of 165434909 is 909434561.

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 76510009 + 88924900 = 8747^2 + 9430^2 .

It is a cyclic number.

It is not a de Polignac number, because 165434909 - 2¹² = 165430813 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165434903) 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, 5474 + ... + 18995.

It is an arithmetic number, because the mean of its divisors is an integer number (41366535).

Almost surely, 2^165434909 is an apocalyptic number.

It is an amenable number.

165434909 is a deficient number, since it is larger than the sum of its proper divisors (31231).

165434909 is an equidigital number, since it uses as much as digits as its factorization.

165434909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31230.

The product of its (nonzero) digits is 116640, while the sum is 41.

The square root of 165434909 is about 12862.1502479173. The cubic root of 165434909 is about 548.9621297850.

It can be divided in two parts, 1654 and 34909, that added together give a palindrome (36563).

The spelling of 165434909 in words is "one hundred sixty-five million, four hundred thirty-four thousand, nine hundred nine".