218449944813 has 4 divisors (see below), whose sum is σ = 291266593088. Its totient is φ = 145633296540.

The previous prime is 218449944773. The next prime is 218449944863. The reversal of 218449944813 is 318449944812.

218449944813 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 218449944813 - 2⁶ = 218449944749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218449944863) 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 in 3 ways as a sum of consecutive naturals, for example, 36408324133 + ... + 36408324138.

It is an arithmetic number, because the mean of its divisors is an integer number (72816648272).

Almost surely, 2^218449944813 is an apocalyptic number.

It is an amenable number.

218449944813 is a deficient number, since it is larger than the sum of its proper divisors (72816648275).

218449944813 is an equidigital number, since it uses as much as digits as its factorization.

218449944813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72816648274.

The product of its digits is 7962624, while the sum is 57.

Subtracting 218449944813 from its reverse (318449944812), we obtain a palindrome (99999999999).

The spelling of 218449944813 in words is "two hundred eighteen billion, four hundred forty-nine million, nine hundred forty-four thousand, eight hundred thirteen".