11999409 has 4 divisors (see below), whose sum is σ = 15999216. Its totient is φ = 7999604.

The previous prime is 11999381. The next prime is 11999423. The reversal of 11999409 is 90499911.

11999409 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 11999409 - 2⁸ = 11999153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11999489) 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, 1999899 + ... + 1999904.

It is an arithmetic number, because the mean of its divisors is an integer number (3999804).

Almost surely, 2^11999409 is an apocalyptic number.

It is an amenable number.

11999409 is a deficient number, since it is larger than the sum of its proper divisors (3999807).

11999409 is an equidigital number, since it uses as much as digits as its factorization.

11999409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3999806.

The product of its (nonzero) digits is 26244, while the sum is 42.

The square root of 11999409 is about 3464.0163105852. The cubic root of 11999409 is about 228.9390899705.

The spelling of 11999409 in words is "eleven million, nine hundred ninety-nine thousand, four hundred nine".