28481 has 4 divisors (see below), whose sum is σ = 30000. Its totient is φ = 26964.

The previous prime is 28477. The next prime is 28493. The reversal of 28481 is 18482.

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: 18482 = 2 ⋅9241.

It is a cyclic number.

It is not a de Polignac number, because 28481 - 2² = 28477 is a prime.

It is a super-2 number, since 2×28481² = 1622334722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 28481.

It is not an unprimeable number, because it can be changed into a prime (28411) 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, 731 + ... + 768.

It is an arithmetic number, because the mean of its divisors is an integer number (7500).

2²⁸⁴⁸¹ is an apocalyptic number.

It is an amenable number.

28481 is a deficient number, since it is larger than the sum of its proper divisors (1519).

28481 is a wasteful number, since it uses less digits than its factorization.

28481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1518.

The product of its digits is 512, while the sum is 23.

The square root of 28481 is about 168.7631476360. The cubic root of 28481 is about 30.5387843072.

Subtracting from 28481 its reverse (18482), we obtain a palindrome (9999).

The spelling of 28481 in words is "twenty-eight thousand, four hundred eighty-one".