31531344313481 has 2 divisors, whose sum is σ = 31531344313482. Its totient is φ = 31531344313480.

The previous prime is 31531344313477. The next prime is 31531344313519. The reversal of 31531344313481 is 18431344313513.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16826535264256 + 14704809049225 = 4102016^2 + 3834685^2 .

It is a cyclic number.

It is not a de Polignac number, because 31531344313481 - 2² = 31531344313477 is a prime.

It is a super-3 number, since 3×31531344313481³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (31531344313981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15765672156740 + 15765672156741.

It is an arithmetic number, because the mean of its divisors is an integer number (15765672156741).

Almost surely, 2^{31531344313481} is an apocalyptic number.

It is an amenable number.

31531344313481 is a deficient number, since it is larger than the sum of its proper divisors (1).

31531344313481 is an equidigital number, since it uses as much as digits as its factorization.

31531344313481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 622080, while the sum is 44.

Adding to 31531344313481 its reverse (18431344313513), we get a palindrome (49962688626994).

The spelling of 31531344313481 in words is "thirty-one trillion, five hundred thirty-one billion, three hundred forty-four million, three hundred thirteen thousand, four hundred eighty-one".