115209 has 16 divisors (see below), whose sum is σ = 181440. Its totient is φ = 72000.

The previous prime is 115201. The next prime is 115211. The reversal of 115209 is 902511.

It is not a de Polignac number, because 115209 - 2³ = 115201 is a prime.

It is a super-2 number, since 2×115209² = 26546227362, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 115191 and 115200.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 115209.

It is not an unprimeable number, because it can be changed into a prime (115201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 334 + ... + 584.

It is an arithmetic number, because the mean of its divisors is an integer number (11340).

2¹¹⁵²⁰⁹ is an apocalyptic number.

It is an amenable number.

115209 is a deficient number, since it is larger than the sum of its proper divisors (66231).

115209 is a wasteful number, since it uses less digits than its factorization.

115209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277 (or 271 counting only the distinct ones).

The product of its (nonzero) digits is 90, while the sum is 18.

The square root of 115209 is about 339.4245129627. The cubic root of 115209 is about 48.6588830570.

It can be divided in two parts, 115 and 209, that added together give a square (324 = 18²).

The spelling of 115209 in words is "one hundred fifteen thousand, two hundred nine".