28287306 has 20 divisors (see below), whose sum is σ = 63384882. Its totient is φ = 9429048.

The previous prime is 28287289. The next prime is 28287341. The reversal of 28287306 is 60378282.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 23184225 + 5103081 = 4815^2 + 2259^2 .

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon 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 9 ways as a sum of consecutive naturals, for example, 87145 + ... + 87468.

Almost surely, 2^28287306 is an apocalyptic number.

28287306 is an abundant number, since it is smaller than the sum of its proper divisors (35097576).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28287306 is a wasteful number, since it uses less digits than its factorization.

28287306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174627 (or 174618 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 28287306 is about 5318.5812017868. The cubic root of 28287306 is about 304.6939723596.

The spelling of 28287306 in words is "twenty-eight million, two hundred eighty-seven thousand, three hundred six".