18507223181 has 2 divisors, whose sum is σ = 18507223182. Its totient is φ = 18507223180.

The previous prime is 18507223159. The next prime is 18507223187. The reversal of 18507223181 is 18132270581.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18505249156 + 1974025 = 136034^2 + 1405^2 .

It is a cyclic number.

It is not a de Polignac number, because 18507223181 - 2¹⁸ = 18506961037 is a prime.

It is a super-2 number, since 2×18507223181² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18507223187) 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, 9253611590 + 9253611591.

It is an arithmetic number, because the mean of its divisors is an integer number (9253611591).

Almost surely, 2^18507223181 is an apocalyptic number.

It is an amenable number.

18507223181 is a deficient number, since it is larger than the sum of its proper divisors (1).

18507223181 is an equidigital number, since it uses as much as digits as its factorization.

18507223181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26880, while the sum is 38.

The spelling of 18507223181 in words is "eighteen billion, five hundred seven million, two hundred twenty-three thousand, one hundred eighty-one".