18957 has 8 divisors (see below), whose sum is σ = 25920.
Its totient is φ = 12320.
The previous prime is 18947. The next prime is 18959. The reversal of 18957 is 75981.
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 18957 - 28 = 18701 is a prime.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (18959) 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, 169 + ... + 257.
It is an arithmetic number, because the mean of its divisors is an integer number (3240).
218957 is an apocalyptic number.
It is an amenable number.
18957 is a deficient number, since it is larger than the sum of its proper divisors (6963).
18957 is an equidigital number, since it uses as much as digits as its factorization.
18957 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 163.
The product of its digits is 2520, while the sum is 30.
The square root of 18957 is about 137.6844217768.
The cubic root of 18957 is about 26.6638712347.
The spelling of 18957 in words is "eighteen thousand, nine hundred fifty-seven".