28864217 has 2 divisors, whose sum is σ = 28864218. Its totient is φ = 28864216.

The previous prime is 28864207. The next prime is 28864219. The reversal of 28864217 is 71246882.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17547721 + 11316496 = 4189^2 + 3364^2 .

It is a cyclic number.

It is not a de Polignac number, because 28864217 - 2⁴ = 28864201 is a prime.

Together with 28864219, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28864219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14432108 + 14432109.

It is an arithmetic number, because the mean of its divisors is an integer number (14432109).

Almost surely, 2^28864217 is an apocalyptic number.

It is an amenable number.

28864217 is a deficient number, since it is larger than the sum of its proper divisors (1).

28864217 is an equidigital number, since it uses as much as digits as its factorization.

28864217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43008, while the sum is 38.

The square root of 28864217 is about 5372.5428802384. The cubic root of 28864217 is about 306.7514283396.

The spelling of 28864217 in words is "twenty-eight million, eight hundred sixty-four thousand, two hundred seventeen".