28305999 has 24 divisors (see below), whose sum is σ = 42325920. Its totient is φ = 18214848.

The previous prime is 28305983. The next prime is 28306039. The reversal of 28305999 is 99950382.

28305999 is a `hidden beast` number, since 28 + 30 + 599 + 9 = 666.

It is not a de Polignac number, because 28305999 - 2⁴ = 28305983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28305929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55357 + ... + 55865.

It is an arithmetic number, because the mean of its divisors is an integer number (1763580).

Almost surely, 2^28305999 is an apocalyptic number.

28305999 is a deficient number, since it is larger than the sum of its proper divisors (14019921).

28305999 is a wasteful number, since it uses less digits than its factorization.

28305999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719 (or 716 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 45.

The square root of 28305999 is about 5320.3382411272. The cubic root of 28305999 is about 304.7610741928.

The spelling of 28305999 in words is "twenty-eight million, three hundred five thousand, nine hundred ninety-nine".