18561489 has 4 divisors (see below), whose sum is σ = 24748656. Its totient is φ = 12374324.

The previous prime is 18561443. The next prime is 18561503. The reversal of 18561489 is 98416581.

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 18561489 - 2¹² = 18557393 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18561489.

It is not an unprimeable number, because it can be changed into a prime (18561409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3093579 + ... + 3093584.

It is an arithmetic number, because the mean of its divisors is an integer number (6187164).

Almost surely, 2^18561489 is an apocalyptic number.

It is an amenable number.

18561489 is a deficient number, since it is larger than the sum of its proper divisors (6187167).

18561489 is an equidigital number, since it uses as much as digits as its factorization.

18561489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6187166.

The product of its digits is 69120, while the sum is 42.

The square root of 18561489 is about 4308.3046549658. The cubic root of 18561489 is about 264.7713180828.

The spelling of 18561489 in words is "eighteen million, five hundred sixty-one thousand, four hundred eighty-nine".