18468531617 has 2 divisors, whose sum is σ = 18468531618. Its totient is φ = 18468531616.

The previous prime is 18468531577. The next prime is 18468531637. The reversal of 18468531617 is 71613586481.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17571888481 + 896643136 = 132559^2 + 29944^2 .

It is a cyclic number.

It is not a de Polignac number, because 18468531617 - 2¹² = 18468527521 is a prime.

It is not a weakly prime, because it can be changed into another prime (18468531637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9234265808 + 9234265809.

It is an arithmetic number, because the mean of its divisors is an integer number (9234265809).

Almost surely, 2^18468531617 is an apocalyptic number.

It is an amenable number.

18468531617 is a deficient number, since it is larger than the sum of its proper divisors (1).

18468531617 is an equidigital number, since it uses as much as digits as its factorization.

18468531617 is an evil number, because the sum of its binary digits is even.

The product of its digits is 967680, while the sum is 50.

The spelling of 18468531617 in words is "eighteen billion, four hundred sixty-eight million, five hundred thirty-one thousand, six hundred seventeen".