18834509 has 2 divisors, whose sum is σ = 18834510. Its totient is φ = 18834508.

The previous prime is 18834467. The next prime is 18834523. The reversal of 18834509 is 90543881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14822500 + 4012009 = 3850^2 + 2003^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18834509 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 (18836509) 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 as a sum of consecutive naturals, namely, 9417254 + 9417255.

It is an arithmetic number, because the mean of its divisors is an integer number (9417255).

Almost surely, 2^18834509 is an apocalyptic number.

It is an amenable number.

18834509 is a deficient number, since it is larger than the sum of its proper divisors (1).

18834509 is an equidigital number, since it uses as much as digits as its factorization.

18834509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 18834509 is about 4339.8743069356. The cubic root of 18834509 is about 266.0631739827.

The spelling of 18834509 in words is "eighteen million, eight hundred thirty-four thousand, five hundred nine".