28125215 has 16 divisors (see below), whose sum is σ = 36046080. Its totient is φ = 21020160.

The previous prime is 28125203. The next prime is 28125233. The reversal of 28125215 is 51252182.

It is a de Polignac number, because none of the positive numbers 2^k-28125215 is a prime.

It is a congruent number.

It is an unprimeable number.

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, 1367 + ... + 7623.

It is an arithmetic number, because the mean of its divisors is an integer number (2252880).

Almost surely, 2^28125215 is an apocalyptic number.

28125215 is a deficient number, since it is larger than the sum of its proper divisors (7920865).

28125215 is a wasteful number, since it uses less digits than its factorization.

28125215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6322.

The product of its digits is 1600, while the sum is 26.

The square root of 28125215 is about 5303.3211292548. The cubic root of 28125215 is about 304.1108746943.

Adding to 28125215 its reverse (51252182), we get a palindrome (79377397).

The spelling of 28125215 in words is "twenty-eight million, one hundred twenty-five thousand, two hundred fifteen".