18544489 has 4 divisors (see below), whose sum is σ = 18553156. Its totient is φ = 18535824.

The previous prime is 18544483. The next prime is 18544499. The reversal of 18544489 is 98444581.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 98444581 = 229 ⋅429889.

It can be written as a sum of positive squares in 2 ways, for example, as 16810000 + 1734489 = 4100^2 + 1317^2 .

It is a cyclic number.

It is not a de Polignac number, because 18544489 - 2¹¹ = 18542441 is a prime.

It is a super-2 number, since 2×18544489² = 687796144542242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18544483) 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, 1447 + ... + 6259.

It is an arithmetic number, because the mean of its divisors is an integer number (4638289).

Almost surely, 2^18544489 is an apocalyptic number.

It is an amenable number.

18544489 is a deficient number, since it is larger than the sum of its proper divisors (8667).

18544489 is an equidigital number, since it uses as much as digits as its factorization.

18544489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8666.

The product of its digits is 184320, while the sum is 43.

The square root of 18544489 is about 4306.3312691896. The cubic root of 18544489 is about 264.6904609336.

The spelling of 18544489 in words is "eighteen million, five hundred forty-four thousand, four hundred eighty-nine".