16640909 has 12 divisors (see below), whose sum is σ = 17948448. Its totient is φ = 15422400.

The previous prime is 16640879. The next prime is 16640917. The reversal of 16640909 is 90904661.

It is not a de Polignac number, because 16640909 - 2¹² = 16636813 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 (16640969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20114 + ... + 20924.

It is an arithmetic number, because the mean of its divisors is an integer number (1495704).

Almost surely, 2^16640909 is an apocalyptic number.

It is an amenable number.

16640909 is a deficient number, since it is larger than the sum of its proper divisors (1307539).

16640909 is an equidigital number, since it uses as much as digits as its factorization.

16640909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 916 (or 899 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 16640909 is about 4079.3270278319. The cubic root of 16640909 is about 255.3048206649.

The spelling of 16640909 in words is "sixteen million, six hundred forty thousand, nine hundred nine".