18530938409 has 2 divisors, whose sum is σ = 18530938410. Its totient is φ = 18530938408.

The previous prime is 18530938397. The next prime is 18530938453. The reversal of 18530938409 is 90483903581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18421275625 + 109662784 = 135725^2 + 10472^2 .

It is an emirp because it is prime and its reverse (90483903581) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18530938409 - 2¹² = 18530934313 is a prime.

It is not a weakly prime, because it can be changed into another prime (18530968409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9265469204 + 9265469205.

It is an arithmetic number, because the mean of its divisors is an integer number (9265469205).

Almost surely, 2^18530938409 is an apocalyptic number.

It is an amenable number.

18530938409 is a deficient number, since it is larger than the sum of its proper divisors (1).

18530938409 is an equidigital number, since it uses as much as digits as its factorization.

18530938409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 933120, while the sum is 50.

The spelling of 18530938409 in words is "eighteen billion, five hundred thirty million, nine hundred thirty-eight thousand, four hundred nine".