18011 has 8 divisors (see below), whose sum is σ = 21504. Its totient is φ = 14760.

The previous prime is 17989. The next prime is 18013. The reversal of 18011 is 11081.

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

It is a cyclic number.

It is not a de Polignac number, because 18011 - 2¹⁰ = 16987 is a prime.

It is a super-2 number, since 2×18011² = 648792242, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 17983 and 18001.

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, 176 + ... + 258.

It is an arithmetic number, because the mean of its divisors is an integer number (2688).

2¹⁸⁰¹¹ is an apocalyptic number.

18011 is a deficient number, since it is larger than the sum of its proper divisors (3493).

18011 is an equidigital number, since it uses as much as digits as its factorization.

18011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 18011 is about 134.2050669684. The cubic root of 18011 is about 26.2127514023.

Adding to 18011 its reverse (11081), we get a palindrome (29092).

It can be divided in two parts, 180 and 11, that added together give a palindrome (191).

The spelling of 18011 in words is "eighteen thousand, eleven".