16988909 has 4 divisors (see below), whose sum is σ = 19415904. Its totient is φ = 14561916.

The previous prime is 16988903. The next prime is 16988921. The reversal of 16988909 is 90988961.

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 16988909 - 2¹⁶ = 16923373 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16988903) 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, 1213487 + ... + 1213500.

It is an arithmetic number, because the mean of its divisors is an integer number (4853976).

Almost surely, 2^16988909 is an apocalyptic number.

It is an amenable number.

16988909 is a deficient number, since it is larger than the sum of its proper divisors (2426995).

16988909 is an equidigital number, since it uses as much as digits as its factorization.

16988909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2426994.

The product of its (nonzero) digits is 279936, while the sum is 50.

The square root of 16988909 is about 4121.7604248670. The cubic root of 16988909 is about 257.0722290889.

The spelling of 16988909 in words is "sixteen million, nine hundred eighty-eight thousand, nine hundred nine".