18145 has 8 divisors (see below), whose sum is σ = 23040. Its totient is φ = 13680.

The previous prime is 18143. The next prime is 18149. The reversal of 18145 is 54181.

18145 = 38² + 39² + ... + 47².

18145 is a nontrivial binomial coefficient, being equal to C(191, 2).

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

It is not a de Polignac number, because 18145 - 2¹ = 18143 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is an alternating number because its digits alternate between odd and even.

18145 is a lucky number.

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (18143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1 + ... + 190.

It is an arithmetic number, because the mean of its divisors is an integer number (2880).

2¹⁸¹⁴⁵ is an apocalyptic number.

18145 is the 190-th triangular number.

18145 is the 64-th centered nonagonal number.

It is an amenable number.

18145 is a deficient number, since it is larger than the sum of its proper divisors (4895).

18145 is a wasteful number, since it uses less digits than its factorization.

18145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215.

The product of its digits is 160, while the sum is 19.

The square root of 18145 is about 134.7033778344. The cubic root of 18145 is about 26.2775975817.

The spelling of 18145 in words is "eighteen thousand, one hundred forty-five".