281504 has 24 divisors (see below), whose sum is σ = 584640. Its totient is φ = 133056.

The previous prime is 281431. The next prime is 281509. The reversal of 281504 is 405182.

281504 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (281509) by changing a digit.

281504 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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, 377 + ... + 839.

It is an arithmetic number, because the mean of its divisors is an integer number (24360).

2²⁸¹⁵⁰⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 281504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (292320).

281504 is an abundant number, since it is smaller than the sum of its proper divisors (303136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

281504 is a wasteful number, since it uses less digits than its factorization.

281504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 492 (or 484 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 281504 is about 530.5695053431. The cubic root of 281504 is about 65.5382524263.

Adding to 281504 its reverse (405182), we get a palindrome (686686).

The spelling of 281504 in words is "two hundred eighty-one thousand, five hundred four".