28533009 has 4 divisors (see below), whose sum is σ = 38044016. Its totient is φ = 19022004.

The previous prime is 28532971. The next prime is 28533017. The reversal of 28533009 is 90033582.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28533009 - 2¹¹ = 28530961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28533059) 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 3 ways as a sum of consecutive naturals, for example, 4755499 + ... + 4755504.

It is an arithmetic number, because the mean of its divisors is an integer number (9511004).

Almost surely, 2^28533009 is an apocalyptic number.

It is an amenable number.

28533009 is a deficient number, since it is larger than the sum of its proper divisors (9511007).

28533009 is an equidigital number, since it uses as much as digits as its factorization.

28533009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9511006.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 28533009 is about 5341.6298074651. The cubic root of 28533009 is about 305.5736190656.

The spelling of 28533009 in words is "twenty-eight million, five hundred thirty-three thousand, nine".