18427 has 2 divisors, whose sum is σ = 18428. Its totient is φ = 18426.

The previous prime is 18413. The next prime is 18433. The reversal of 18427 is 72481.

It is a strong prime.

It is an emirp because it is prime and its reverse (72481) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18427 is a prime.

It is a Chen prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 18398 and 18407.

It is not a weakly prime, because it can be changed into another prime (18457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9213 + 9214.

It is an arithmetic number, because the mean of its divisors is an integer number (9214).

2¹⁸⁴²⁷ is an apocalyptic number.

18427 is a deficient number, since it is larger than the sum of its proper divisors (1).

18427 is an equidigital number, since it uses as much as digits as its factorization.

18427 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 448, while the sum is 22.

The square root of 18427 is about 135.7460864998. The cubic root of 18427 is about 26.4130292282.

It can be divided in two parts, 1842 and 7, that added together give a square (1849 = 43²).

The spelling of 18427 in words is "eighteen thousand, four hundred twenty-seven".