18839 has 2 divisors, whose sum is σ = 18840.
Its totient is φ = 18838.
The previous prime is 18803. The next prime is 18859. The reversal of 18839 is 93881.
It is a happy number.
It is a strong prime.
It is a cyclic number.
It is not a de Polignac number, because 18839 - 28 = 18583 is a prime.
It is a Chen prime.
It is a plaindrome in base 15.
It is a nialpdrome in base 13.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (18859) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9419 + 9420.
It is an arithmetic number, because the mean of its divisors is an integer number (9420).
218839 is an apocalyptic number.
18839 is a deficient number, since it is larger than the sum of its proper divisors (1).
18839 is an equidigital number, since it uses as much as digits as its factorization.
18839 is an evil number, because the sum of its binary digits is even.
The product of its digits is 1728, while the sum is 29.
The square root of 18839 is about 137.2552366943.
The cubic root of 18839 is about 26.6084319473.
The spelling of 18839 in words is "eighteen thousand, eight hundred thirty-nine".