18897289 has 4 divisors (see below), whose sum is σ = 19163520. Its totient is φ = 18631060.

The previous prime is 18897271. The next prime is 18897311. The reversal of 18897289 is 98279881.

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 18897289 - 2⁷ = 18897161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18897889) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133009 + ... + 133150.

It is an arithmetic number, because the mean of its divisors is an integer number (4790880).

Almost surely, 2^18897289 is an apocalyptic number.

It is an amenable number.

18897289 is a deficient number, since it is larger than the sum of its proper divisors (266231).

18897289 is an equidigital number, since it uses as much as digits as its factorization.

18897289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266230.

The product of its digits is 580608, while the sum is 52.

The square root of 18897289 is about 4347.1012180532. The cubic root of 18897289 is about 266.3584638939.

The spelling of 18897289 in words is "eighteen million, eight hundred ninety-seven thousand, two hundred eighty-nine".