12135246561 has 24 divisors (see below), whose sum is σ = 18836816544. Its totient is φ = 7500620160.

The previous prime is 12135246559. The next prime is 12135246623. The reversal of 12135246561 is 16564253121.

12135246561 is a `hidden beast` number, since 1 + 2 + 1 + 3 + 52 + 46 + 561 = 666.

It is not a de Polignac number, because 12135246561 - 2¹ = 12135246559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12135246061) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 581655 + ... + 602156.

It is an arithmetic number, because the mean of its divisors is an integer number (784867356).

Almost surely, 2^12135246561 is an apocalyptic number.

It is an amenable number.

12135246561 is a deficient number, since it is larger than the sum of its proper divisors (6701569983).

12135246561 is a wasteful number, since it uses less digits than its factorization.

12135246561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1183901 (or 1183898 counting only the distinct ones).

The product of its digits is 43200, while the sum is 36.

Adding to 12135246561 its reverse (16564253121), we get a palindrome (28699499682).

The spelling of 12135246561 in words is "twelve billion, one hundred thirty-five million, two hundred forty-six thousand, five hundred sixty-one".