18231008161 has 2 divisors, whose sum is σ = 18231008162. Its totient is φ = 18231008160.

The previous prime is 18231008149. The next prime is 18231008179. The reversal of 18231008161 is 16180013281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16165851025 + 2065157136 = 127145^2 + 45444^2 .

It is a cyclic number.

It is not a de Polignac number, because 18231008161 - 2⁵ = 18231008129 is a prime.

It is not a weakly prime, because it can be changed into another prime (18231008141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9115504080 + 9115504081.

It is an arithmetic number, because the mean of its divisors is an integer number (9115504081).

Almost surely, 2^18231008161 is an apocalyptic number.

It is an amenable number.

18231008161 is a deficient number, since it is larger than the sum of its proper divisors (1).

18231008161 is an equidigital number, since it uses as much as digits as its factorization.

18231008161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 31.

The spelling of 18231008161 in words is "eighteen billion, two hundred thirty-one million, eight thousand, one hundred sixty-one".