281823 has 4 divisors (see below), whose sum is σ = 375768. Its totient is φ = 187880.

The previous prime is 281807. The next prime is 281833. The reversal of 281823 is 328182.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 281823 - 2⁴ = 281807 is a prime.

It is a D-number.

It is a plaindrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 281793 and 281802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (281803) 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 in 3 ways as a sum of consecutive naturals, for example, 46968 + ... + 46973.

It is an arithmetic number, because the mean of its divisors is an integer number (93942).

2²⁸¹⁸²³ is an apocalyptic number.

281823 is a deficient number, since it is larger than the sum of its proper divisors (93945).

281823 is an equidigital number, since it uses as much as digits as its factorization.

281823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93944.

The product of its digits is 768, while the sum is 24.

The square root of 281823 is about 530.8700405937. The cubic root of 281823 is about 65.5629990378.

The spelling of 281823 in words is "two hundred eighty-one thousand, eight hundred twenty-three".