18287251117 has 2 divisors, whose sum is σ = 18287251118. Its totient is φ = 18287251116.

The previous prime is 18287251111. The next prime is 18287251139. The reversal of 18287251117 is 71115278281.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18064972836 + 222278281 = 134406^2 + 14909^2 .

It is a cyclic number.

It is not a de Polignac number, because 18287251117 - 2³ = 18287251109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18287251111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9143625558 + 9143625559.

It is an arithmetic number, because the mean of its divisors is an integer number (9143625559).

Almost surely, 2^18287251117 is an apocalyptic number.

It is an amenable number.

18287251117 is a deficient number, since it is larger than the sum of its proper divisors (1).

18287251117 is an equidigital number, since it uses as much as digits as its factorization.

18287251117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 62720, while the sum is 43.

The spelling of 18287251117 in words is "eighteen billion, two hundred eighty-seven million, two hundred fifty-one thousand, one hundred seventeen".