18028505 has 16 divisors (see below), whose sum is σ = 23744448. Its totient is φ = 13032000.

The previous prime is 18028499. The next prime is 18028519. The reversal of 18028505 is 50582081.

It is not a de Polignac number, because 18028505 - 2¹⁰ = 18027481 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 9050 + ... + 10860.

It is an arithmetic number, because the mean of its divisors is an integer number (1484028).

Almost surely, 2^18028505 is an apocalyptic number.

It is an amenable number.

18028505 is a deficient number, since it is larger than the sum of its proper divisors (5715943).

18028505 is a wasteful number, since it uses less digits than its factorization.

18028505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2008.

The product of its (nonzero) digits is 3200, while the sum is 29.

The square root of 18028505 is about 4245.9987046630. The cubic root of 18028505 is about 262.2124076319.

The spelling of 18028505 in words is "eighteen million, twenty-eight thousand, five hundred five".