28280065 has 16 divisors (see below), whose sum is σ = 37138176. Its totient is φ = 20502400.

The previous prime is 28280047. The next prime is 28280069. The reversal of 28280065 is 56008282.

It is not a de Polignac number, because 28280065 - 2¹⁷ = 28148993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28280069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23109 + ... + 24301.

It is an arithmetic number, because the mean of its divisors is an integer number (2321136).

Almost surely, 2^28280065 is an apocalyptic number.

It is an amenable number.

28280065 is a deficient number, since it is larger than the sum of its proper divisors (8858111).

28280065 is a wasteful number, since it uses less digits than its factorization.

28280065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1640.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 28280065 is about 5317.9004315613. The cubic root of 28280065 is about 304.6679715645.

The spelling of 28280065 in words is "twenty-eight million, two hundred eighty thousand, sixty-five".