18378781067 has 2 divisors, whose sum is σ = 18378781068. Its totient is φ = 18378781066.

The previous prime is 18378781019. The next prime is 18378781093. The reversal of 18378781067 is 76018787381.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (76018787381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18378781067 - 2²⁰ = 18377732491 is a prime.

It is not a weakly prime, because it can be changed into another prime (18378783067) 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, 9189390533 + 9189390534.

It is an arithmetic number, because the mean of its divisors is an integer number (9189390534).

Almost surely, 2^18378781067 is an apocalyptic number.

18378781067 is a deficient number, since it is larger than the sum of its proper divisors (1).

18378781067 is an equidigital number, since it uses as much as digits as its factorization.

18378781067 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3161088, while the sum is 56.

The spelling of 18378781067 in words is "eighteen billion, three hundred seventy-eight million, seven hundred eighty-one thousand, sixty-seven".