16564109 has 2 divisors, whose sum is σ = 16564110. Its totient is φ = 16564108.

The previous prime is 16564099. The next prime is 16564111. The reversal of 16564109 is 90146561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15038884 + 1525225 = 3878^2 + 1235^2 .

It is a cyclic number.

It is not a de Polignac number, because 16564109 - 2¹² = 16560013 is a prime.

Together with 16564111, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16564129) 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 as a sum of consecutive naturals, namely, 8282054 + 8282055.

It is an arithmetic number, because the mean of its divisors is an integer number (8282055).

Almost surely, 2^16564109 is an apocalyptic number.

It is an amenable number.

16564109 is a deficient number, since it is larger than the sum of its proper divisors (1).

16564109 is an equidigital number, since it uses as much as digits as its factorization.

16564109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 16564109 is about 4069.9028243927. The cubic root of 16564109 is about 254.9114597133.

The spelling of 16564109 in words is "sixteen million, five hundred sixty-four thousand, one hundred nine".