28517315 has 4 divisors (see below), whose sum is σ = 34220784. Its totient is φ = 22813848.

The previous prime is 28517311. The next prime is 28517327. The reversal of 28517315 is 51371582.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28517315 - 2² = 28517311 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28517311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2851727 + ... + 2851736.

It is an arithmetic number, because the mean of its divisors is an integer number (8555196).

Almost surely, 2^28517315 is an apocalyptic number.

28517315 is a deficient number, since it is larger than the sum of its proper divisors (5703469).

28517315 is an equidigital number, since it uses as much as digits as its factorization.

28517315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5703468.

The product of its digits is 8400, while the sum is 32.

The square root of 28517315 is about 5340.1605781100. The cubic root of 28517315 is about 305.5175839438.

Adding to 28517315 its reverse (51371582), we get a palindrome (79888897).

The spelling of 28517315 in words is "twenty-eight million, five hundred seventeen thousand, three hundred fifteen".