218138441639 has 2 divisors, whose sum is σ = 218138441640. Its totient is φ = 218138441638.

The previous prime is 218138441627. The next prime is 218138441701. The reversal of 218138441639 is 936144831812.

It is a happy number.

218138441639 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 218138441639 - 2²⁸ = 217870006183 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218138444639) 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, 109069220819 + 109069220820.

It is an arithmetic number, because the mean of its divisors is an integer number (109069220820).

Almost surely, 2^218138441639 is an apocalyptic number.

218138441639 is a deficient number, since it is larger than the sum of its proper divisors (1).

218138441639 is an equidigital number, since it uses as much as digits as its factorization.

218138441639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 995328, while the sum is 50.

The spelling of 218138441639 in words is "two hundred eighteen billion, one hundred thirty-eight million, four hundred forty-one thousand, six hundred thirty-nine".