28715 has 4 divisors (see below), whose sum is σ = 34464. Its totient is φ = 22968.

The previous prime is 28711. The next prime is 28723. The reversal of 28715 is 51782.

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 28715 - 2² = 28711 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28711) by changing a digit.

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, 2867 + ... + 2876.

It is an arithmetic number, because the mean of its divisors is an integer number (8616).

2²⁸⁷¹⁵ is an apocalyptic number.

28715 is a deficient number, since it is larger than the sum of its proper divisors (5749).

28715 is an equidigital number, since it uses as much as digits as its factorization.

28715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5748.

The product of its digits is 560, while the sum is 23.

The square root of 28715 is about 169.4550087781. The cubic root of 28715 is about 30.6221918847.

The spelling of 28715 in words is "twenty-eight thousand, seven hundred fifteen".