16897809 has 4 divisors (see below), whose sum is σ = 22530416. Its totient is φ = 11265204.

The previous prime is 16897799. The next prime is 16897817. The reversal of 16897809 is 90879861.

It is a happy number.

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 not a de Polignac number, because 16897809 - 2⁸ = 16897553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16897889) 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, 2816299 + ... + 2816304.

It is an arithmetic number, because the mean of its divisors is an integer number (5632604).

Almost surely, 2^16897809 is an apocalyptic number.

It is an amenable number.

16897809 is a deficient number, since it is larger than the sum of its proper divisors (5632607).

16897809 is an equidigital number, since it uses as much as digits as its factorization.

16897809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5632606.

The product of its (nonzero) digits is 217728, while the sum is 48.

The square root of 16897809 is about 4110.6944668754. The cubic root of 16897809 is about 256.6119039479.

The spelling of 16897809 in words is "sixteen million, eight hundred ninety-seven thousand, eight hundred nine".