163209 has 4 divisors (see below), whose sum is σ = 217616. Its totient is φ = 108804.

The previous prime is 163199. The next prime is 163211. The reversal of 163209 is 902361.

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, and also an emirpimes, since its reverse is a distinct semiprime: 902361 = 3 ⋅300787.

It is not a de Polignac number, because 163209 - 2⁴ = 163193 is a prime.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (163249) 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, 27199 + ... + 27204.

It is an arithmetic number, because the mean of its divisors is an integer number (54404).

2¹⁶³²⁰⁹ is an apocalyptic number.

It is an amenable number.

163209 is a deficient number, since it is larger than the sum of its proper divisors (54407).

163209 is an equidigital number, since it uses as much as digits as its factorization.

163209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54406.

The product of its (nonzero) digits is 324, while the sum is 21.

The square root of 163209 is about 403.9913365408. The cubic root of 163209 is about 54.6488928602.

The spelling of 163209 in words is "one hundred sixty-three thousand, two hundred nine".