18489321 has 6 divisors (see below), whose sum is σ = 26706810. Its totient is φ = 12326208.

The previous prime is 18489311. The next prime is 18489347. The reversal of 18489321 is 12398481.

It can be written as a sum of positive squares in only one way, i.e., 9272025 + 9217296 = 3045^2 + 3036^2 .

It is not a de Polignac number, because 18489321 - 2⁶ = 18489257 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18489301) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1027176 + ... + 1027193.

It is an arithmetic number, because the mean of its divisors is an integer number (4451135).

Almost surely, 2^18489321 is an apocalyptic number.

It is an amenable number.

18489321 is a deficient number, since it is larger than the sum of its proper divisors (8217489).

18489321 is a wasteful number, since it uses less digits than its factorization.

18489321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2054375 (or 2054372 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 18489321 is about 4299.9210457868. The cubic root of 18489321 is about 264.4277243402.

The spelling of 18489321 in words is "eighteen million, four hundred eighty-nine thousand, three hundred twenty-one".