31311021130121 has 2 divisors, whose sum is σ = 31311021130122. Its totient is φ = 31311021130120.

The previous prime is 31311021130117. The next prime is 31311021130139. The reversal of 31311021130121 is 12103112011313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21629987148025 + 9681033982096 = 4650805^2 + 3111436^2 .

It is an emirp because it is prime and its reverse (12103112011313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31311021130121 - 2² = 31311021130117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31311021130093 and 31311021130102.

It is not a weakly prime, because it can be changed into another prime (31311021930121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15655510565060 + 15655510565061.

It is an arithmetic number, because the mean of its divisors is an integer number (15655510565061).

Almost surely, 2^{31311021130121} is an apocalyptic number.

It is an amenable number.

31311021130121 is a deficient number, since it is larger than the sum of its proper divisors (1).

31311021130121 is an equidigital number, since it uses as much as digits as its factorization.

31311021130121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 20.

Adding to 31311021130121 its reverse (12103112011313), we get a palindrome (43414133141434).

The spelling of 31311021130121 in words is "thirty-one trillion, three hundred eleven billion, twenty-one million, one hundred thirty thousand, one hundred twenty-one".