12891530561 has 16 divisors (see below), whose sum is σ = 15879932544. Its totient is φ = 10191256704.

The previous prime is 12891530551. The next prime is 12891530599. The reversal of 12891530561 is 16503519821.

It is a cyclic number.

It is not a de Polignac number, because 12891530561 - 2¹⁴ = 12891514177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12891530551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49190 + ... + 167936.

It is an arithmetic number, because the mean of its divisors is an integer number (992495784).

Almost surely, 2^12891530561 is an apocalyptic number.

It is an amenable number.

12891530561 is a deficient number, since it is larger than the sum of its proper divisors (2988401983).

12891530561 is a wasteful number, since it uses less digits than its factorization.

12891530561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119960.

The product of its (nonzero) digits is 64800, while the sum is 41.

The spelling of 12891530561 in words is "twelve billion, eight hundred ninety-one million, five hundred thirty thousand, five hundred sixty-one".