18744289 has 4 divisors (see below), whose sum is σ = 18879280. Its totient is φ = 18609300.

The previous prime is 18744269. The next prime is 18744293. The reversal of 18744289 is 98244781.

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, and also an emirpimes, since its reverse is a distinct semiprime: 98244781 = 2687 ⋅36563.

It is a cyclic number.

It is not a de Polignac number, because 18744289 - 2¹⁵ = 18711521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18744269) 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, 67287 + ... + 67564.

It is an arithmetic number, because the mean of its divisors is an integer number (4719820).

Almost surely, 2^18744289 is an apocalyptic number.

It is an amenable number.

18744289 is a deficient number, since it is larger than the sum of its proper divisors (134991).

18744289 is a wasteful number, since it uses less digits than its factorization.

18744289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134990.

The product of its digits is 129024, while the sum is 43.

The square root of 18744289 is about 4329.4675192222. The cubic root of 18744289 is about 265.6376669207.

The spelling of 18744289 in words is "eighteen million, seven hundred forty-four thousand, two hundred eighty-nine".