12121312531 has 2 divisors, whose sum is σ = 12121312532. Its totient is φ = 12121312530.

The previous prime is 12121312513. The next prime is 12121312597. The reversal of 12121312531 is 13521312121.

12121312531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with previous prime (12121312513) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12121312531 - 2⁵ = 12121312499 is a prime.

It is a super-2 number, since 2×12121312531² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12121319531) 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 as a sum of consecutive naturals, namely, 6060656265 + 6060656266.

It is an arithmetic number, because the mean of its divisors is an integer number (6060656266).

Almost surely, 2^12121312531 is an apocalyptic number.

12121312531 is a deficient number, since it is larger than the sum of its proper divisors (1).

12121312531 is an equidigital number, since it uses as much as digits as its factorization.

12121312531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 360, while the sum is 22.

Adding to 12121312531 its reverse (13521312121), we get a palindrome (25642624652).

The spelling of 12121312531 in words is "twelve billion, one hundred twenty-one million, three hundred twelve thousand, five hundred thirty-one".