28215985 has 16 divisors (see below), whose sum is σ = 40032000. Its totient is φ = 18680256.

The previous prime is 28215973. The next prime is 28215989. The reversal of 28215985 is 58951282.

It is not a de Polignac number, because 28215985 - 2⁵ = 28215953 is a prime.

It is a super-2 number, since 2×28215985² = 1592283619040450, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28215989) 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, 12885 + ... + 14914.

It is an arithmetic number, because the mean of its divisors is an integer number (2502000).

Almost surely, 2^28215985 is an apocalyptic number.

It is an amenable number.

28215985 is a deficient number, since it is larger than the sum of its proper divisors (11816015).

28215985 is a wasteful number, since it uses less digits than its factorization.

28215985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27840.

The product of its digits is 57600, while the sum is 40.

The square root of 28215985 is about 5311.8720805381. The cubic root of 28215985 is about 304.4376810982.

The spelling of 28215985 in words is "twenty-eight million, two hundred fifteen thousand, nine hundred eighty-five".