18157 has 4 divisors (see below), whose sum is σ = 18496.
Its totient is φ = 17820.
The previous prime is 18149. The next prime is 18169. The reversal of 18157 is 75181.
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 18157 - 23 = 18149 is a prime.
It is a Duffinian number.
It is a plaindrome in base 14.
It is a nialpdrome in base 12.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (18127) 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, 69 + ... + 202.
It is an arithmetic number, because the mean of its divisors is an integer number (4624).
218157 is an apocalyptic number.
It is an amenable number.
18157 is a deficient number, since it is larger than the sum of its proper divisors (339).
18157 is an equidigital number, since it uses as much as digits as its factorization.
18157 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 338.
The product of its digits is 280, while the sum is 22.
The square root of 18157 is about 134.7479127853.
The cubic root of 18157 is about 26.2833891070.
The spelling of 18157 in words is "eighteen thousand, one hundred fifty-seven".