164509 has 4 divisors (see below), whose sum is σ = 174204. Its totient is φ = 154816.

The previous prime is 164503. The next prime is 164513. The reversal of 164509 is 905461.

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 120409 + 44100 = 347^2 + 210^2 .

It is a cyclic number.

It is not a de Polignac number, because 164509 - 2⁵ = 164477 is a prime.

It is a super-2 number, since 2×164509² = 54126422162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164503) 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, 4822 + ... + 4855.

It is an arithmetic number, because the mean of its divisors is an integer number (43551).

2¹⁶⁴⁵⁰⁹ is an apocalyptic number.

It is an amenable number.

164509 is a deficient number, since it is larger than the sum of its proper divisors (9695).

164509 is an equidigital number, since it uses as much as digits as its factorization.

164509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9694.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 164509 is about 405.5970907193. The cubic root of 164509 is about 54.7936066209.

The spelling of 164509 in words is "one hundred sixty-four thousand, five hundred nine".