12111556701681 has 6 divisors (see below), whose sum is σ = 17494470791330. Its totient is φ = 8074371134448.

The previous prime is 12111556701679. The next prime is 12111556701779. The reversal of 12111556701681 is 18610765511121.

12111556701681 is a `hidden beast` number, since 1 + 2 + 1 + 1 + 1 + 5 + 567 + 0 + 1 + 6 + 81 = 666.

12111556701681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 7060929732081 + 5050626969600 = 2657241^2 + 2247360^2 .

It is not a de Polignac number, because 12111556701681 - 2¹ = 12111556701679 is a prime.

It is a super-2 number, since 2×12111556701681² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12111556701641) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 672864261196 + ... + 672864261213.

Almost surely, 2^{12111556701681} is an apocalyptic number.

It is an amenable number.

12111556701681 is a deficient number, since it is larger than the sum of its proper divisors (5382914089649).

12111556701681 is a wasteful number, since it uses less digits than its factorization.

12111556701681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1345728522415 (or 1345728522412 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 45.

The spelling of 12111556701681 in words is "twelve trillion, one hundred eleven billion, five hundred fifty-six million, seven hundred one thousand, six hundred eighty-one".