28317217 has 2 divisors, whose sum is σ = 28317218. Its totient is φ = 28317216.

The previous prime is 28317203. The next prime is 28317221. The reversal of 28317217 is 71271382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17715681 + 10601536 = 4209^2 + 3256^2 .

It is a cyclic number.

It is not a de Polignac number, because 28317217 - 2²³ = 19928609 is a prime.

It is not a weakly prime, because it can be changed into another prime (28317287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14158608 + 14158609.

It is an arithmetic number, because the mean of its divisors is an integer number (14158609).

Almost surely, 2^28317217 is an apocalyptic number.

It is an amenable number.

28317217 is a deficient number, since it is larger than the sum of its proper divisors (1).

28317217 is an equidigital number, since it uses as much as digits as its factorization.

28317217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4704, while the sum is 31.

The square root of 28317217 is about 5321.3923929739. The cubic root of 28317217 is about 304.8013290070.

Adding to 28317217 its reverse (71271382), we get a palindrome (99588599).

The spelling of 28317217 in words is "twenty-eight million, three hundred seventeen thousand, two hundred seventeen".