18368353517 has 4 divisors (see below), whose sum is σ = 18370211196. Its totient is φ = 18366495840.

The previous prime is 18368353499. The next prime is 18368353567. The reversal of 18368353517 is 71535386381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71535386381 = 5861 ⋅12205321.

It can be written as a sum of positive squares in 2 ways, for example, as 5652182761 + 12716170756 = 75181^2 + 112766^2 .

It is a cyclic number.

It is not a de Polignac number, because 18368353517 - 2⁸ = 18368353261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18368353567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 913928 + ... + 933809.

It is an arithmetic number, because the mean of its divisors is an integer number (4592552799).

Almost surely, 2^18368353517 is an apocalyptic number.

It is an amenable number.

18368353517 is a deficient number, since it is larger than the sum of its proper divisors (1857679).

18368353517 is an equidigital number, since it uses as much as digits as its factorization.

18368353517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1857678.

The product of its digits is 1814400, while the sum is 50.

The spelling of 18368353517 in words is "eighteen billion, three hundred sixty-eight million, three hundred fifty-three thousand, five hundred seventeen".