16409009 has 4 divisors (see below), whose sum is σ = 16482816. Its totient is φ = 16335204.

The previous prime is 16408999. The next prime is 16409039. The reversal of 16409009 is 90090461.

16409009 is nontrivially palindromic in base 12.

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: 90090461 = 43 ⋅2095127.

It is a cyclic number.

It is not a de Polignac number, because 16409009 - 2⁴ = 16408993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16409039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36569 + ... + 37014.

It is an arithmetic number, because the mean of its divisors is an integer number (4120704).

Almost surely, 2^16409009 is an apocalyptic number.

It is an amenable number.

16409009 is a deficient number, since it is larger than the sum of its proper divisors (73807).

16409009 is an equidigital number, since it uses as much as digits as its factorization.

16409009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73806.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 16409009 is about 4050.8035005416. The cubic root of 16409009 is about 254.1133321516.

The spelling of 16409009 in words is "sixteen million, four hundred nine thousand, nine".