228309 has 4 divisors (see below), whose sum is σ = 304416.
Its totient is φ = 152204.
The previous prime is 228307. The next prime is 228311. The reversal of 228309 is 903822.
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 an interprime number because it is at equal distance from previous prime (228307) and next prime (228311).
It is a cyclic number.
It is not a de Polignac number, because 228309 - 21 = 228307 is a prime.
It is a D-number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (228301) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (13) of ones.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38049 + ... + 38054.
It is an arithmetic number, because the mean of its divisors is an integer number (76104).
2228309 is an apocalyptic number.
It is an amenable number.
228309 is a deficient number, since it is larger than the sum of its proper divisors (76107).
228309 is an equidigital number, since it uses as much as digits as its factorization.
228309 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 76106.
The product of its (nonzero) digits is 864, while the sum is 24.
The square root of 228309 is about 477.8169105421.
The cubic root of 228309 is about 61.1187331785.
The spelling of 228309 in words is "two hundred twenty-eight thousand, three hundred nine".