28516217 has 2 divisors, whose sum is σ = 28516218. Its totient is φ = 28516216.

The previous prime is 28516153. The next prime is 28516231. The reversal of 28516217 is 71261582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21864976 + 6651241 = 4676^2 + 2579^2 .

It is a cyclic number.

It is not a de Polignac number, because 28516217 - 2⁶ = 28516153 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28516247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14258108 + 14258109.

It is an arithmetic number, because the mean of its divisors is an integer number (14258109).

Almost surely, 2^28516217 is an apocalyptic number.

It is an amenable number.

28516217 is a deficient number, since it is larger than the sum of its proper divisors (1).

28516217 is an equidigital number, since it uses as much as digits as its factorization.

28516217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6720, while the sum is 32.

The square root of 28516217 is about 5340.0577712231. The cubic root of 28516217 is about 305.5136627868.

Adding to 28516217 its reverse (71261582), we get a palindrome (99777799).

The spelling of 28516217 in words is "twenty-eight million, five hundred sixteen thousand, two hundred seventeen".