109209 has 8 divisors (see below), whose sum is σ = 148320. Its totient is φ = 71456.

The previous prime is 109201. The next prime is 109211. The reversal of 109209 is 902901.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 109209 - 2³ = 109201 is a prime.

It is a Curzon number.

It is a plaindrome in base 15.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 109209.

It is not an unprimeable number, because it can be changed into a prime (109201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 132 + ... + 485.

It is an arithmetic number, because the mean of its divisors is an integer number (18540).

2¹⁰⁹²⁰⁹ is an apocalyptic number.

109209 is the 177-th nonagonal number.

It is an amenable number.

109209 is a deficient number, since it is larger than the sum of its proper divisors (39111).

109209 is an equidigital number, since it uses as much as digits as its factorization.

109209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 679.

The product of its (nonzero) digits is 162, while the sum is 21.

The square root of 109209 is about 330.4678501761. The cubic root of 109209 is about 47.7990732942.

The spelling of 109209 in words is "one hundred nine thousand, two hundred nine".