31321121323021 has 2 divisors, whose sum is σ = 31321121323022. Its totient is φ = 31321121323020.

The previous prime is 31321121323013. The next prime is 31321121323031. The reversal of 31321121323021 is 12032312112313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21541303670121 + 9779817652900 = 4641261^2 + 3127270^2 .

It is a cyclic number.

It is not a de Polignac number, because 31321121323021 - 2³ = 31321121323013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31321121323031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15660560661510 + 15660560661511.

It is an arithmetic number, because the mean of its divisors is an integer number (15660560661511).

Almost surely, 2^{31321121323021} is an apocalyptic number.

It is an amenable number.

31321121323021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31321121323021 is an equidigital number, since it uses as much as digits as its factorization.

31321121323021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 31321121323021 its reverse (12032312112313), we get a palindrome (43353433435334).

The spelling of 31321121323021 in words is "thirty-one trillion, three hundred twenty-one billion, one hundred twenty-one million, three hundred twenty-three thousand, twenty-one".