28523 has 4 divisors (see below), whose sum is σ = 31128. Its totient is φ = 25920.

The previous prime is 28517. The next prime is 28537. The reversal of 28523 is 32582.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28523 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 13.

It is a junction number, because it is equal to n+sod(n) for n = 28495 and 28504.

It is not an unprimeable number, because it can be changed into a prime (28513) 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, 1286 + ... + 1307.

It is an arithmetic number, because the mean of its divisors is an integer number (7782).

2²⁸⁵²³ is an apocalyptic number.

28523 is a deficient number, since it is larger than the sum of its proper divisors (2605).

28523 is a wasteful number, since it uses less digits than its factorization.

28523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2604.

The product of its digits is 480, while the sum is 20.

The square root of 28523 is about 168.8875365443. The cubic root of 28523 is about 30.5537884500.

It can be divided in two parts, 285 and 23, that multiplied together give a triangular number (6555 = T₁₁₄).

The spelling of 28523 in words is "twenty-eight thousand, five hundred twenty-three".