209109 has 8 divisors (see below), whose sum is σ = 285472. Its totient is φ = 136080.

The previous prime is 209089. The next prime is 209123. The reversal of 209109 is 901902.

It is a happy number.

209109 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 209109 - 2¹¹ = 207061 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209159) 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, 682 + ... + 939.

It is an arithmetic number, because the mean of its divisors is an integer number (35684).

2²⁰⁹¹⁰⁹ is an apocalyptic number.

It is an amenable number.

209109 is a deficient number, since it is larger than the sum of its proper divisors (76363).

209109 is a wasteful number, since it uses less digits than its factorization.

209109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1667.

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

The square root of 209109 is about 457.2843754164. The cubic root of 209109 is about 59.3550363170.

The spelling of 209109 in words is "two hundred nine thousand, one hundred nine".