31221412513 has 2 divisors, whose sum is σ = 31221412514. Its totient is φ = 31221412512.

The previous prime is 31221412459. The next prime is 31221412553. The reversal of 31221412513 is 31521412213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30454787169 + 766625344 = 174513^2 + 27688^2 .

It is a cyclic number.

It is not a de Polignac number, because 31221412513 - 2²⁵ = 31187858081 is a prime.

It is not a weakly prime, because it can be changed into another prime (31221412553) 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, 15610706256 + 15610706257.

It is an arithmetic number, because the mean of its divisors is an integer number (15610706257).

Almost surely, 2^31221412513 is an apocalyptic number.

It is an amenable number.

31221412513 is a deficient number, since it is larger than the sum of its proper divisors (1).

31221412513 is an equidigital number, since it uses as much as digits as its factorization.

31221412513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 25.

Adding to 31221412513 its reverse (31521412213), we get a palindrome (62742824726).

The spelling of 31221412513 in words is "thirty-one billion, two hundred twenty-one million, four hundred twelve thousand, five hundred thirteen".