228009 has 4 divisors (see below), whose sum is σ = 304016. Its totient is φ = 152004.

The previous prime is 227993. The next prime is 228013. The reversal of 228009 is 900822.

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 228009 - 2⁴ = 227993 is a prime.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (228049) 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, 37999 + ... + 38004.

It is an arithmetic number, because the mean of its divisors is an integer number (76004).

2²²⁸⁰⁰⁹ is an apocalyptic number.

It is an amenable number.

228009 is a deficient number, since it is larger than the sum of its proper divisors (76007).

228009 is an equidigital number, since it uses as much as digits as its factorization.

228009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76006.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 228009 is about 477.5028795725. The cubic root of 228009 is about 61.0919512632.

The spelling of 228009 in words is "two hundred twenty-eight thousand, nine".