18818345225 has 12 divisors (see below), whose sum is σ = 23965418124. Its totient is φ = 14647792320.

The previous prime is 18818345213. The next prime is 18818345261. The reversal of 18818345225 is 52254381881.

It can be written as a sum of positive squares in 6 ways, for example, as 2514119881 + 16304225344 = 50141^2 + 127688^2 .

It is a de Polignac number, because none of the positive numbers 2^k-18818345225 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 18818345225.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10171154 + ... + 10173003.

It is an arithmetic number, because the mean of its divisors is an integer number (1997118177).

Almost surely, 2^18818345225 is an apocalyptic number.

It is an amenable number.

18818345225 is a deficient number, since it is larger than the sum of its proper divisors (5147072899).

18818345225 is a wasteful number, since it uses less digits than its factorization.

18818345225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20344204 (or 20344199 counting only the distinct ones).

The product of its digits is 614400, while the sum is 47.

The spelling of 18818345225 in words is "eighteen billion, eight hundred eighteen million, three hundred forty-five thousand, two hundred twenty-five".