281239 has 4 divisors (see below), whose sum is σ = 321424. Its totient is φ = 241056.

The previous prime is 281233. The next prime is 281243. The reversal of 281239 is 932182.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 932182 = 2 ⋅466091.

It is a cyclic number.

It is not a de Polignac number, because 281239 - 2⁵ = 281207 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (281233) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20082 + ... + 20095.

It is an arithmetic number, because the mean of its divisors is an integer number (80356).

2²⁸¹²³⁹ is an apocalyptic number.

281239 is a deficient number, since it is larger than the sum of its proper divisors (40185).

281239 is an equidigital number, since it uses as much as digits as its factorization.

281239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40184.

The product of its digits is 864, while the sum is 25.

The square root of 281239 is about 530.3197148890. The cubic root of 281239 is about 65.5176806765.

The spelling of 281239 in words is "two hundred eighty-one thousand, two hundred thirty-nine".