18189550 has 24 divisors (see below), whose sum is σ = 35305776. Its totient is φ = 6959040.

The previous prime is 18189539. The next prime is 18189551. The reversal of 18189550 is 5598181.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18189551) 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 11 ways as a sum of consecutive naturals, for example, 6759 + ... + 9058.

It is an arithmetic number, because the mean of its divisors is an integer number (1471074).

Almost surely, 2^18189550 is an apocalyptic number.

18189550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18189550 is a deficient number, since it is larger than the sum of its proper divisors (17116226).

18189550 is a wasteful number, since it uses less digits than its factorization.

18189550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15852 (or 15847 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 37.

The square root of 18189550 is about 4264.9208667923. The cubic root of 18189550 is about 262.9908578219.

The spelling of 18189550 in words is "eighteen million, one hundred eighty-nine thousand, five hundred fifty".