28230009 has 4 divisors (see below), whose sum is σ = 37640016. Its totient is φ = 18820004.

The previous prime is 28229989. The next prime is 28230011. The reversal of 28230009 is 90003282.

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 a cyclic number.

It is not a de Polignac number, because 28230009 - 2¹¹ = 28227961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28230089) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4704999 + ... + 4705004.

It is an arithmetic number, because the mean of its divisors is an integer number (9410004).

Almost surely, 2^28230009 is an apocalyptic number.

It is an amenable number.

28230009 is a deficient number, since it is larger than the sum of its proper divisors (9410007).

28230009 is an equidigital number, since it uses as much as digits as its factorization.

28230009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9410006.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 28230009 is about 5313.1919784627. The cubic root of 28230009 is about 304.4881102775.

The spelling of 28230009 in words is "twenty-eight million, two hundred thirty thousand, nine".