28581315 has 16 divisors (see below), whose sum is σ = 52263168. Its totient is φ = 13065696.

The previous prime is 28581313. The next prime is 28581317. The reversal of 28581315 is 51318582.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28581313) and next prime (28581317).

It is not a de Polignac number, because 28581315 - 2¹ = 28581313 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28581313) 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 15 ways as a sum of consecutive naturals, for example, 135997 + ... + 136206.

It is an arithmetic number, because the mean of its divisors is an integer number (3266448).

Almost surely, 2^28581315 is an apocalyptic number.

28581315 is a deficient number, since it is larger than the sum of its proper divisors (23681853).

28581315 is a wasteful number, since it uses less digits than its factorization.

28581315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272218.

The product of its digits is 9600, while the sum is 33.

The square root of 28581315 is about 5346.1495489745. The cubic root of 28581315 is about 305.7459658492.

Adding to 28581315 its reverse (51318582), we get a palindrome (79899897).

The spelling of 28581315 in words is "twenty-eight million, five hundred eighty-one thousand, three hundred fifteen".