228249509 has 2 divisors, whose sum is σ = 228249510. Its totient is φ = 228249508.

The previous prime is 228249487. The next prime is 228249529. The reversal of 228249509 is 905942822.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 123698884 + 104550625 = 11122^2 + 10225^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-228249509 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (228249529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114124754 + 114124755.

It is an arithmetic number, because the mean of its divisors is an integer number (114124755).

Almost surely, 2^228249509 is an apocalyptic number.

It is an amenable number.

228249509 is a deficient number, since it is larger than the sum of its proper divisors (1).

228249509 is an equidigital number, since it uses as much as digits as its factorization.

228249509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 103680, while the sum is 41.

The square root of 228249509 is about 15107.9286800011. The cubic root of 228249509 is about 611.1342410113.

The spelling of 228249509 in words is "two hundred twenty-eight million, two hundred forty-nine thousand, five hundred nine".