16908409 has 4 divisors (see below), whose sum is σ = 19323904. Its totient is φ = 14492916.

The previous prime is 16908383. The next prime is 16908443. The reversal of 16908409 is 90480961.

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 16908409 - 2⁹ = 16907897 is a prime.

It is a super-2 number, since 2×16908409² = 571788589822562, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16908509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1207737 + ... + 1207750.

It is an arithmetic number, because the mean of its divisors is an integer number (4830976).

Almost surely, 2^16908409 is an apocalyptic number.

It is an amenable number.

16908409 is a deficient number, since it is larger than the sum of its proper divisors (2415495).

16908409 is an equidigital number, since it uses as much as digits as its factorization.

16908409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2415494.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 16908409 is about 4111.9835845976. The cubic root of 16908409 is about 256.6655503034.

The spelling of 16908409 in words is "sixteen million, nine hundred eight thousand, four hundred nine".