12499312581 has 40 divisors (see below), whose sum is σ = 21428732160. Its totient is φ = 7112502432.

The previous prime is 12499312571. The next prime is 12499312589. The reversal of 12499312581 is 18521399421.

12499312581 is a `hidden beast` number, since 12 + 49 + 9 + 3 + 12 + 581 = 666.

12499312581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12499312581 - 2⁶ = 12499312517 is a prime.

It is a super-2 number, since 2×12499312581² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12499312589) 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 39 ways as a sum of consecutive naturals, for example, 89395 + ... + 181631.

It is an arithmetic number, because the mean of its divisors is an integer number (535718304).

Almost surely, 2^12499312581 is an apocalyptic number.

It is an amenable number.

12499312581 is a deficient number, since it is larger than the sum of its proper divisors (8929419579).

12499312581 is an equidigital number, since it uses as much as digits as its factorization.

12499312581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92495 (or 92486 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The spelling of 12499312581 in words is "twelve billion, four hundred ninety-nine million, three hundred twelve thousand, five hundred eighty-one".