18015 has 8 divisors (see below), whose sum is σ = 28848. Its totient is φ = 9600.

The previous prime is 18013. The next prime is 18041. The reversal of 18015 is 51081.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18015 - 2¹ = 18013 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15), and also a Moran number because the ratio is a prime number: 1201 = 18015 / (1 + 8 + 0 + 1 + 5).

It is a nialpdrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 17985 and 18003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 586 + ... + 615.

It is an arithmetic number, because the mean of its divisors is an integer number (3606).

2¹⁸⁰¹⁵ is an apocalyptic number.

18015 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

18015 is a deficient number, since it is larger than the sum of its proper divisors (10833).

18015 is a wasteful number, since it uses less digits than its factorization.

18015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1209.

The product of its (nonzero) digits is 40, while the sum is 15.

The square root of 18015 is about 134.2199687081. The cubic root of 18015 is about 26.2146917581.

Multiplying 18015 by its product of nonzero digits (40), we get a triangular number (720600 = T₁₂₀₀).

Adding to 18015 its reverse (51081), we get a palindrome (69096).

The spelling of 18015 in words is "eighteen thousand, fifteen".