28308517 has 2 divisors, whose sum is σ = 28308518. Its totient is φ = 28308516.

The previous prime is 28308503. The next prime is 28308521. The reversal of 28308517 is 71580382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25090081 + 3218436 = 5009^2 + 1794^2 .

It is a cyclic number.

It is not a de Polignac number, because 28308517 - 2¹⁵ = 28275749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28308557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14154258 + 14154259.

It is an arithmetic number, because the mean of its divisors is an integer number (14154259).

Almost surely, 2^28308517 is an apocalyptic number.

It is an amenable number.

28308517 is a deficient number, since it is larger than the sum of its proper divisors (1).

28308517 is an equidigital number, since it uses as much as digits as its factorization.

28308517 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 28308517 is about 5320.5748749548. The cubic root of 28308517 is about 304.7701107417.

Adding to 28308517 its reverse (71580382), we get a palindrome (99888899).

The spelling of 28308517 in words is "twenty-eight million, three hundred eight thousand, five hundred seventeen".