28684305 has 24 divisors (see below), whose sum is σ = 53545128. Its totient is φ = 14121216.

The previous prime is 28684291. The next prime is 28684307. The reversal of 28684305 is 50348682.

It can be written as a sum of positive squares in 4 ways, for example, as 40401 + 28643904 = 201^2 + 5352^2 .

It is not a de Polignac number, because 28684305 - 2⁷ = 28684177 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28684305.

It is not an unprimeable number, because it can be changed into a prime (28684307) 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 23 ways as a sum of consecutive naturals, for example, 23932 + ... + 25101.

It is an arithmetic number, because the mean of its divisors is an integer number (2231047).

Almost surely, 2^28684305 is an apocalyptic number.

It is an amenable number.

28684305 is a deficient number, since it is larger than the sum of its proper divisors (24860823).

28684305 is a wasteful number, since it uses less digits than its factorization.

28684305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49057 (or 49054 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 28684305 is about 5355.7730534443. The cubic root of 28684305 is about 306.1127676136.

The spelling of 28684305 in words is "twenty-eight million, six hundred eighty-four thousand, three hundred five".