18518516683309 has 2 divisors, whose sum is σ = 18518516683310. Its totient is φ = 18518516683308.

The previous prime is 18518516683273. The next prime is 18518516683399. The reversal of 18518516683309 is 90338661581581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14231869425225 + 4286647258084 = 3772515^2 + 2070422^2 .

It is a cyclic number.

It is not a de Polignac number, because 18518516683309 - 2¹⁵ = 18518516650541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18518516683399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9259258341654 + 9259258341655.

It is an arithmetic number, because the mean of its divisors is an integer number (9259258341655).

Almost surely, 2^{18518516683309} is an apocalyptic number.

It is an amenable number.

18518516683309 is a deficient number, since it is larger than the sum of its proper divisors (1).

18518516683309 is an equidigital number, since it uses as much as digits as its factorization.

18518516683309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 37324800, while the sum is 64.

The spelling of 18518516683309 in words is "eighteen trillion, five hundred eighteen billion, five hundred sixteen million, six hundred eighty-three thousand, three hundred nine".