16564243 has 4 divisors (see below), whose sum is σ = 16630488. Its totient is φ = 16498000.

The previous prime is 16564241. The next prime is 16564253. The reversal of 16564243 is 34246561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34246561 = 173 ⋅197957.

It is a cyclic number.

It is not a de Polignac number, because 16564243 - 2¹ = 16564241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16564241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32746 + ... + 33247.

It is an arithmetic number, because the mean of its divisors is an integer number (4157622).

Almost surely, 2^16564243 is an apocalyptic number.

16564243 is a deficient number, since it is larger than the sum of its proper divisors (66245).

16564243 is an equidigital number, since it uses as much as digits as its factorization.

16564243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66244.

The product of its digits is 17280, while the sum is 31.

The square root of 16564243 is about 4069.9192866690. The cubic root of 16564243 is about 254.9121471040.

It can be divided in two parts, 16564 and 243, that added together give a 5-th power (16807 = 7⁵).

The spelling of 16564243 in words is "sixteen million, five hundred sixty-four thousand, two hundred forty-three".