18516681851 has 2 divisors, whose sum is σ = 18516681852. Its totient is φ = 18516681850.

The previous prime is 18516681823. The next prime is 18516681863. The reversal of 18516681851 is 15818661581.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18516681851 - 2³⁰ = 17442940027 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18516681851.

It is not a weakly prime, because it can be changed into another prime (18516681811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9258340925 + 9258340926.

It is an arithmetic number, because the mean of its divisors is an integer number (9258340926).

Almost surely, 2^18516681851 is an apocalyptic number.

18516681851 is a deficient number, since it is larger than the sum of its proper divisors (1).

18516681851 is an equidigital number, since it uses as much as digits as its factorization.

18516681851 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 460800, while the sum is 50.

The spelling of 18516681851 in words is "eighteen billion, five hundred sixteen million, six hundred eighty-one thousand, eight hundred fifty-one".