18101 has 4 divisors (see below), whose sum is σ = 18912. Its totient is φ = 17292.

The previous prime is 18097. The next prime is 18119. The reversal of 18101 is 10181.

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 18101 - 2² = 18097 is a prime.

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

It is a Duffinian number.

It is a plaindrome in base 11 and base 15.

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 18101.

It is not an unprimeable number, because it can be changed into a prime (18121) 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, 371 + ... + 416.

It is an arithmetic number, because the mean of its divisors is an integer number (4728).

2¹⁸¹⁰¹ is an apocalyptic number.

It is an amenable number.

18101 is a deficient number, since it is larger than the sum of its proper divisors (811).

18101 is an equidigital number, since it uses as much as digits as its factorization.

18101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 810.

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

The square root of 18101 is about 134.5399568901. The cubic root of 18101 is about 26.2563401163.

Adding to 18101 its reverse (10181), we get a palindrome (28282).

The spelling of 18101 in words is "eighteen thousand, one hundred one".