12566618505681 has 16 divisors (see below), whose sum is σ = 17235099033600. Its totient is φ = 8140506571728.

The previous prime is 12566618505589. The next prime is 12566618505689. The reversal of 12566618505681 is 18650581666521.

12566618505681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12566618505681 - 2¹¹ = 12566618503633 is a prime.

It is a super-2 number, since 2×12566618505681² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (12566618505689) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 320573761 + ... + 320612958.

It is an arithmetic number, because the mean of its divisors is an integer number (1077193689600).

Almost surely, 2^{12566618505681} is an apocalyptic number.

It is an amenable number.

12566618505681 is a deficient number, since it is larger than the sum of its proper divisors (4668480527919).

12566618505681 is a wasteful number, since it uses less digits than its factorization.

12566618505681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 641186908.

The product of its (nonzero) digits is 20736000, while the sum is 60.

The spelling of 12566618505681 in words is "twelve trillion, five hundred sixty-six billion, six hundred eighteen million, five hundred five thousand, six hundred eighty-one".