28120615 has 16 divisors (see below), whose sum is σ = 34572096. Its totient is φ = 21952000.

The previous prime is 28120607. The next prime is 28120619. The reversal of 28120615 is 51602182.

It is not a de Polignac number, because 28120615 - 2³ = 28120607 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28120615.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28120619) 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, 39765 + ... + 40465.

It is an arithmetic number, because the mean of its divisors is an integer number (2160756).

Almost surely, 2^28120615 is an apocalyptic number.

28120615 is a deficient number, since it is larger than the sum of its proper divisors (6451481).

28120615 is a wasteful number, since it uses less digits than its factorization.

28120615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 890.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 28120615 is about 5302.8874210189. The cubic root of 28120615 is about 304.0942942427.

Adding to 28120615 its reverse (51602182), we get a palindrome (79722797).

The spelling of 28120615 in words is "twenty-eight million, one hundred twenty thousand, six hundred fifteen".