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18841 = 83227

18841 has 4 divisors (see below), whose sum is σ = 19152. Its totient is φ = 18532.

The previous prime is 18839. The next prime is 18859. The reversal of 18841 is 14881.

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, and also an emirpimes, since its reverse is a distinct semiprime: 14881 = 23647.

It is a cyclic number.

It is not a de Polignac number, because 18841 - 21 = 18839 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a nialpdrome in base 12 and base 13.

It is not an unprimeable number, because it can be changed into a prime (18041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31 + ... + 196.

It is an arithmetic number, because the mean of its divisors is an integer number (4788).

218841 is an apocalyptic number.

It is an amenable number.

18841 is a deficient number, since it is larger than the sum of its proper divisors (311).

18841 is an equidigital number, since it uses as much as digits as its factorization.

18841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310.

The product of its digits is 256, while the sum is 22.

The square root of 18841 is about 137.2625221974. The cubic root of 18841 is about 26.6093735220.

The spelling of 18841 in words is "eighteen thousand, eight hundred forty-one".

Divisors: 1 83 227 18841