18383818393 has 2 divisors, whose sum is σ = 18383818394. Its totient is φ = 18383818392.

The previous prime is 18383818363. The next prime is 18383818399. The reversal of 18383818393 is 39381838381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14941884169 + 3441934224 = 122237^2 + 58668^2 .

It is an emirp because it is prime and its reverse (39381838381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18383818393 - 2²⁵ = 18350263961 is a prime.

It is a super-3 number, since 3×18383818393³ (a number of 32 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (18383818399) 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, 9191909196 + 9191909197.

It is an arithmetic number, because the mean of its divisors is an integer number (9191909197).

Almost surely, 2^18383818393 is an apocalyptic number.

It is an amenable number.

18383818393 is a deficient number, since it is larger than the sum of its proper divisors (1).

18383818393 is an equidigital number, since it uses as much as digits as its factorization.

18383818393 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2985984, while the sum is 55.

The spelling of 18383818393 in words is "eighteen billion, three hundred eighty-three million, eight hundred eighteen thousand, three hundred ninety-three".