25645767218 has 16 divisors (see below), whose sum is σ = 40761493440. Its totient is φ = 12067542000.

The previous prime is 25645767209. The next prime is 25645767223. The reversal of 25645767218 is 81276754652.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 25645767218.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2228993 + ... + 2240468.

It is an arithmetic number, because the mean of its divisors is an integer number (2547593340).

Almost surely, 2^25645767218 is an apocalyptic number.

25645767218 is a deficient number, since it is larger than the sum of its proper divisors (15115726222).

25645767218 is a wasteful number, since it uses less digits than its factorization.

25645767218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4469633.

The product of its digits is 5644800, while the sum is 53.

The spelling of 25645767218 in words is "twenty-five billion, six hundred forty-five million, seven hundred sixty-seven thousand, two hundred eighteen".