18999242617 has 2 divisors, whose sum is σ = 18999242618. Its totient is φ = 18999242616.

The previous prime is 18999242609. The next prime is 18999242629. The reversal of 18999242617 is 71624299981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18963768681 + 35473936 = 137709^2 + 5956^2 .

It is a cyclic number.

It is not a de Polignac number, because 18999242617 - 2³ = 18999242609 is a prime.

It is not a weakly prime, because it can be changed into another prime (18999242677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9499621308 + 9499621309.

It is an arithmetic number, because the mean of its divisors is an integer number (9499621309).

Almost surely, 2^18999242617 is an apocalyptic number.

It is an amenable number.

18999242617 is a deficient number, since it is larger than the sum of its proper divisors (1).

18999242617 is an equidigital number, since it uses as much as digits as its factorization.

18999242617 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3919104, while the sum is 58.

The spelling of 18999242617 in words is "eighteen billion, nine hundred ninety-nine million, two hundred forty-two thousand, six hundred seventeen".