18028493 has 4 divisors (see below), whose sum is σ = 20604000. Its totient is φ = 15452988.

The previous prime is 18028477. The next prime is 18028499. The reversal of 18028493 is 39482081.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18028493 - 2⁴ = 18028477 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18028499) 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 3 ways as a sum of consecutive naturals, for example, 1287743 + ... + 1287756.

It is an arithmetic number, because the mean of its divisors is an integer number (5151000).

Almost surely, 2^18028493 is an apocalyptic number.

It is an amenable number.

18028493 is a deficient number, since it is larger than the sum of its proper divisors (2575507).

18028493 is an equidigital number, since it uses as much as digits as its factorization.

18028493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2575506.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 18028493 is about 4245.9972915677. The cubic root of 18028493 is about 262.2123494546.

The spelling of 18028493 in words is "eighteen million, twenty-eight thousand, four hundred ninety-three".