28305317 has 4 divisors (see below), whose sum is σ = 28315980. Its totient is φ = 28294656.

The previous prime is 28305313. The next prime is 28305349. The reversal of 28305317 is 71350382.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 8288641 + 20016676 = 2879^2 + 4474^2 .

It is a cyclic number.

It is not a de Polignac number, because 28305317 - 2² = 28305313 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28305317.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28305313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2159 + ... + 7827.

It is an arithmetic number, because the mean of its divisors is an integer number (7078995).

Almost surely, 2^28305317 is an apocalyptic number.

It is an amenable number.

28305317 is a deficient number, since it is larger than the sum of its proper divisors (10663).

28305317 is an equidigital number, since it uses as much as digits as its factorization.

28305317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10662.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 28305317 is about 5320.2741470717. The cubic root of 28305317 is about 304.7586265524.

Adding to 28305317 its reverse (71350382), we get a palindrome (99655699).

The spelling of 28305317 in words is "twenty-eight million, three hundred five thousand, three hundred seventeen".