12546456581 has 2 divisors, whose sum is σ = 12546456582. Its totient is φ = 12546456580.

The previous prime is 12546456547. The next prime is 12546456589. The reversal of 12546456581 is 18565464521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11840704225 + 705752356 = 108815^2 + 26566^2 .

It is a cyclic number.

It is not a de Polignac number, because 12546456581 - 2²⁶ = 12479347717 is a prime.

It is a super-2 number, since 2×12546456581² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12546456589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6273228290 + 6273228291.

It is an arithmetic number, because the mean of its divisors is an integer number (6273228291).

Almost surely, 2^12546456581 is an apocalyptic number.

It is an amenable number.

12546456581 is a deficient number, since it is larger than the sum of its proper divisors (1).

12546456581 is an equidigital number, since it uses as much as digits as its factorization.

12546456581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152000, while the sum is 47.

The spelling of 12546456581 in words is "twelve billion, five hundred forty-six million, four hundred fifty-six thousand, five hundred eighty-one".