12180577581 has 20 divisors (see below), whose sum is σ = 18273798972. Its totient is φ = 8085521088.

The previous prime is 12180577561. The next prime is 12180577603. The reversal of 12180577581 is 18577508121.

12180577581 is a `hidden beast` number, since 1 + 2 + 18 + 0 + 57 + 7 + 581 = 666.

12180577581 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 2 ways, for example, as 3165075081 + 9015502500 = 56259^2 + 94950^2 .

It is not a de Polignac number, because 12180577581 - 2⁶ = 12180577517 is a prime.

It is a super-2 number, since 2×12180577581² (a number of 21 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12180577561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 303826 + ... + 341571.

Almost surely, 2^12180577581 is an apocalyptic number.

It is an amenable number.

12180577581 is a deficient number, since it is larger than the sum of its proper divisors (6093221391).

12180577581 is an equidigital number, since it uses as much as digits as its factorization.

12180577581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 645642 (or 645633 counting only the distinct ones).

The product of its (nonzero) digits is 156800, while the sum is 45.

The spelling of 12180577581 in words is "twelve billion, one hundred eighty million, five hundred seventy-seven thousand, five hundred eighty-one".