28574509 has 4 divisors (see below), whose sum is σ = 28586304. Its totient is φ = 28562716.

The previous prime is 28574443. The next prime is 28574519. The reversal of 28574509 is 90547582.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 28574509 - 2¹⁵ = 28541741 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28574519) 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, 787 + ... + 7600.

It is an arithmetic number, because the mean of its divisors is an integer number (7146576).

Almost surely, 2^28574509 is an apocalyptic number.

It is an amenable number.

28574509 is a deficient number, since it is larger than the sum of its proper divisors (11795).

28574509 is an equidigital number, since it uses as much as digits as its factorization.

28574509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11794.

The product of its (nonzero) digits is 100800, while the sum is 40.

The square root of 28574509 is about 5345.5129781902. The cubic root of 28574509 is about 305.7216950714.

The spelling of 28574509 in words is "twenty-eight million, five hundred seventy-four thousand, five hundred nine".