169509 has 4 divisors (see below), whose sum is σ = 226016. Its totient is φ = 113004.

The previous prime is 169501. The next prime is 169523. The reversal of 169509 is 905961.

169509 is nontrivially palindromic in base 6.

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 not a de Polignac number, because 169509 - 2³ = 169501 is a prime.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a zygodrome in base 6.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (169501) 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, 28249 + ... + 28254.

It is an arithmetic number, because the mean of its divisors is an integer number (56504).

2¹⁶⁹⁵⁰⁹ is an apocalyptic number.

It is an amenable number.

169509 is a deficient number, since it is larger than the sum of its proper divisors (56507).

169509 is an equidigital number, since it uses as much as digits as its factorization.

169509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56506.

The product of its (nonzero) digits is 2430, while the sum is 30.

The square root of 169509 is about 411.7147070485. The cubic root of 169509 is about 55.3431983508.

The spelling of 169509 in words is "one hundred sixty-nine thousand, five hundred nine".