18216320835149 has 4 divisors (see below), whose sum is σ = 18216329437020. Its totient is φ = 18216312233280.

The previous prime is 18216320835143. The next prime is 18216320835179. The reversal of 18216320835149 is 94153802361281.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 18117877380100 + 98443455049 = 4256510^2 + 313757^2 .

It is a cyclic number.

It is not a de Polignac number, because 18216320835149 - 2³² = 18212025867853 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18216320835149.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18216320835143) 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, 1354307 + ... + 6186015.

It is an arithmetic number, because the mean of its divisors is an integer number (4554082359255).

Almost surely, 2^{18216320835149} is an apocalyptic number.

It is an amenable number.

18216320835149 is a deficient number, since it is larger than the sum of its proper divisors (8601871).

18216320835149 is an equidigital number, since it uses as much as digits as its factorization.

18216320835149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8601870.

The product of its (nonzero) digits is 2488320, while the sum is 53.

The spelling of 18216320835149 in words is "eighteen trillion, two hundred sixteen billion, three hundred twenty million, eight hundred thirty-five thousand, one hundred forty-nine".