31311202320121 has 2 divisors, whose sum is σ = 31311202320122. Its totient is φ = 31311202320120.

The previous prime is 31311202320077. The next prime is 31311202320137. The reversal of 31311202320121 is 12102320211313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25809194075625 + 5502008244496 = 5080275^2 + 2345636^2 .

It is a cyclic number.

It is not a de Polignac number, because 31311202320121 - 2¹³ = 31311202311929 is a prime.

It is a super-2 number, since 2×31311202320121² (a number of 28 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31311202320092 and 31311202320101.

It is not a weakly prime, because it can be changed into another prime (31311202320161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15655601160060 + 15655601160061.

It is an arithmetic number, because the mean of its divisors is an integer number (15655601160061).

Almost surely, 2^{31311202320121} is an apocalyptic number.

It is an amenable number.

31311202320121 is a deficient number, since it is larger than the sum of its proper divisors (1).

31311202320121 is an equidigital number, since it uses as much as digits as its factorization.

31311202320121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 22.

Adding to 31311202320121 its reverse (12102320211313), we get a palindrome (43413522531434).

The spelling of 31311202320121 in words is "thirty-one trillion, three hundred eleven billion, two hundred two million, three hundred twenty thousand, one hundred twenty-one".