18238489 has 4 divisors (see below), whose sum is σ = 18340560. Its totient is φ = 18136420.

The previous prime is 18238483. The next prime is 18238523. The reversal of 18238489 is 98483281.

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: 98483281 = 13 ⋅7575637.

It is a cyclic number.

It is not a de Polignac number, because 18238489 - 2¹³ = 18230297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18238483) 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, 50767 + ... + 51124.

It is an arithmetic number, because the mean of its divisors is an integer number (4585140).

Almost surely, 2^18238489 is an apocalyptic number.

It is an amenable number.

18238489 is a deficient number, since it is larger than the sum of its proper divisors (102071).

18238489 is a wasteful number, since it uses less digits than its factorization.

18238489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102070.

The product of its digits is 110592, while the sum is 43.

The square root of 18238489 is about 4270.6543995037. The cubic root of 18238489 is about 263.2265056547.

The spelling of 18238489 in words is "eighteen million, two hundred thirty-eight thousand, four hundred eighty-nine".