18312728897 has 2 divisors, whose sum is σ = 18312728898. Its totient is φ = 18312728896.

The previous prime is 18312728851. The next prime is 18312728923. The reversal of 18312728897 is 79882721381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17296458256 + 1016270641 = 131516^2 + 31879^2 .

It is an emirp because it is prime and its reverse (79882721381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18312728897 - 2⁸ = 18312728641 is a prime.

It is not a weakly prime, because it can be changed into another prime (18312721897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9156364448 + 9156364449.

It is an arithmetic number, because the mean of its divisors is an integer number (9156364449).

Almost surely, 2^18312728897 is an apocalyptic number.

It is an amenable number.

18312728897 is a deficient number, since it is larger than the sum of its proper divisors (1).

18312728897 is an equidigital number, since it uses as much as digits as its factorization.

18312728897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2709504, while the sum is 56.

The spelling of 18312728897 in words is "eighteen billion, three hundred twelve million, seven hundred twenty-eight thousand, eight hundred ninety-seven".