18189549 has 32 divisors (see below), whose sum is σ = 31043840. Its totient is φ = 10310976.

The previous prime is 18189539. The next prime is 18189551. The reversal of 18189549 is 94598181.

It is not a de Polignac number, because 18189549 - 2⁷ = 18189421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18189539) 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 31 ways as a sum of consecutive naturals, for example, 29367 + ... + 29979.

It is an arithmetic number, because the mean of its divisors is an integer number (970120).

Almost surely, 2^18189549 is an apocalyptic number.

It is an amenable number.

18189549 is a deficient number, since it is larger than the sum of its proper divisors (12854291).

18189549 is a wasteful number, since it uses less digits than its factorization.

18189549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786 (or 780 counting only the distinct ones).

The product of its digits is 103680, while the sum is 45.

The square root of 18189549 is about 4264.9207495568. The cubic root of 18189549 is about 262.9908530025.

The spelling of 18189549 in words is "eighteen million, one hundred eighty-nine thousand, five hundred forty-nine".