18071 has 4 divisors (see below), whose sum is σ = 19152. Its totient is φ = 16992.

The previous prime is 18061. The next prime is 18077. The reversal of 18071 is 17081.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18071 - 2¹⁰ = 17047 is a prime.

It is a super-2 number, since 2×18071² = 653122082, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 1063 = 18071 / (1 + 8 + 0 + 7 + 1).

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 18071.

It is not an unprimeable number, because it can be changed into a prime (18077) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 515 + ... + 548.

It is an arithmetic number, because the mean of its divisors is an integer number (4788).

2¹⁸⁰⁷¹ is an apocalyptic number.

18071 is a deficient number, since it is larger than the sum of its proper divisors (1081).

18071 is a wasteful number, since it uses less digits than its factorization.

18071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1080.

The product of its (nonzero) digits is 56, while the sum is 17.

The square root of 18071 is about 134.4284196143. The cubic root of 18071 is about 26.2418266315.

Subtracting from 18071 its reverse (17081), we obtain a triangular number (990 = T₄₄).

The spelling of 18071 in words is "eighteen thousand, seventy-one".