28717 has 6 divisors (see below), whose sum is σ = 31598.
Its totient is φ = 25944.
The previous prime is 28711. The next prime is 28723. The reversal of 28717 is 71782.
It is a happy number.
It is an interprime number because it is at equal distance from previous prime (28711) and next prime (28723).
It can be written as a sum of positive squares in only one way, i.e., 19881 + 8836 = 141^2 + 94^2
It is not a de Polignac number, because 28717 - 211 = 26669 is a prime.
It is a Duffinian number.
It is a junction number, because it is equal to n+sod(n) for n = 28691 and 28700.
It is a congruent 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 5 ways as a sum of consecutive naturals, for example, 588 + ... + 634.
228717 is an apocalyptic number.
It is an amenable number.
28717 is a deficient number, since it is larger than the sum of its proper divisors (2881).
28717 is an equidigital number, since it uses as much as digits as its factorization.
28717 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 107 (or 60 counting only the distinct ones).
The product of its digits is 784, while the sum is 25.
The square root of 28717 is about 169.4609099468.
The cubic root of 28717 is about 30.6229028135.
The spelling of 28717 in words is "twenty-eight thousand, seven hundred seventeen".