18047 has 2 divisors, whose sum is σ = 18048.
Its totient is φ = 18046.
The previous prime is 18043. The next prime is 18049. The reversal of 18047 is 74081.
It is a happy number.
It is a strong prime.
It is a cyclic number.
It is not a de Polignac number, because 18047 - 22 = 18043 is a prime.
Together with 18049, it forms a pair of twin primes.
It is a Chen prime.
It is a plaindrome in base 16.
It is a nialpdrome in base 15.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (18041) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9023 + 9024.
It is an arithmetic number, because the mean of its divisors is an integer number (9024).
218047 is an apocalyptic number.
18047 is a deficient number, since it is larger than the sum of its proper divisors (1).
18047 is an equidigital number, since it uses as much as digits as its factorization.
18047 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 224, while the sum is 20.
The square root of 18047 is about 134.3391231176.
The cubic root of 18047 is about 26.2302042741.
The spelling of 18047 in words is "eighteen thousand, forty-seven".