28565 has 8 divisors (see below), whose sum is σ = 35640. Its totient is φ = 21952.

The previous prime is 28559. The next prime is 28571. The reversal of 28565 is 56582.

28565 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (28559) and next prime (28571).

It can be written as a sum of positive squares in 4 ways, for example, as 10609 + 17956 = 103^2 + 134^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28565 - 2⁴ = 28549 is a prime.

28565 is an undulating number in base 14.

28565 is strictly pandigital in base 6.

It is a Curzon number.

It is a zygodrome in base 3.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47 + ... + 243.

It is an arithmetic number, because the mean of its divisors is an integer number (4455).

2²⁸⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

28565 is a deficient number, since it is larger than the sum of its proper divisors (7075).

28565 is a wasteful number, since it uses less digits than its factorization.

28565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231.

The product of its digits is 2400, while the sum is 26.

The square root of 28565 is about 169.0118339052. The cubic root of 28565 is about 30.5687778710.

The spelling of 28565 in words is "twenty-eight thousand, five hundred sixty-five".