11923209 has 9 divisors (see below), whose sum is σ = 17237389. Its totient is φ = 7941900.

The previous prime is 11923207. The next prime is 11923211. The reversal of 11923209 is 90232911.

The square root of 11923209 is 3453.

It is a perfect power (a square), and thus also a powerful number.

11923209 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (11923207) and next prime (11923211).

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 11923209 - 2¹ = 11923207 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (11923201) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 9784 + ... + 10934.

Almost surely, 2^11923209 is an apocalyptic number.

11923209 is the 3453-rd square number.

11923209 is the 1727-th centered octagonal number.

It is an amenable number.

11923209 is a deficient number, since it is larger than the sum of its proper divisors (5314180).

11923209 is an frugal number, since it uses more digits than its factorization.

11923209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2308 (or 1154 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The cubic root of 11923209 is about 228.4534489168.

The spelling of 11923209 in words is "eleven million, nine hundred twenty-three thousand, two hundred nine".