11409 has 4 divisors (see below), whose sum is σ = 15216. Its totient is φ = 7604.

The previous prime is 11399. The next prime is 11411. The reversal of 11409 is 90411.

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: 90411 = 3 ⋅30137.

It is a cyclic number.

It is not a de Polignac number, because 11409 - 2⁴ = 11393 is a prime.

It is a D-number.

It is a nialpdrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (11489) 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, 1899 + ... + 1904.

It is an arithmetic number, because the mean of its divisors is an integer number (3804).

2¹¹⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

11409 is a deficient number, since it is larger than the sum of its proper divisors (3807).

11409 is an equidigital number, since it uses as much as digits as its factorization.

11409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3806.

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 11409 is about 106.8129205668. The cubic root of 11409 is about 22.5120922655.

The spelling of 11409 in words is "eleven thousand, four hundred nine".