12536661618 has 48 divisors (see below), whose sum is σ = 29261109696. Its totient is φ = 3856260960.

The previous prime is 12536661581. The next prime is 12536661661. The reversal of 12536661618 is 81616663521.

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 23 ways as a sum of consecutive naturals, for example, 1062813 + ... + 1074543.

It is an arithmetic number, because the mean of its divisors is an integer number (609606452).

Almost surely, 2^12536661618 is an apocalyptic number.

12536661618 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

12536661618 is an abundant number, since it is smaller than the sum of its proper divisors (16724448078).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12536661618 is a wasteful number, since it uses less digits than its factorization.

12536661618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16319 (or 16316 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The spelling of 12536661618 in words is "twelve billion, five hundred thirty-six million, six hundred sixty-one thousand, six hundred eighteen".