31313200023221 has 2 divisors, whose sum is σ = 31313200023222. Its totient is φ = 31313200023220.

The previous prime is 31313200023151. The next prime is 31313200023269. The reversal of 31313200023221 is 12232000231313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27132524614321 + 4180675408900 = 5208889^2 + 2044670^2 .

It is a cyclic number.

It is not a de Polignac number, because 31313200023221 - 2²² = 31313195828917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31313200026221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15656600011610 + 15656600011611.

It is an arithmetic number, because the mean of its divisors is an integer number (15656600011611).

Almost surely, 2^{31313200023221} is an apocalyptic number.

It is an amenable number.

31313200023221 is a deficient number, since it is larger than the sum of its proper divisors (1).

31313200023221 is an equidigital number, since it uses as much as digits as its factorization.

31313200023221 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 23.

Adding to 31313200023221 its reverse (12232000231313), we get a palindrome (43545200254534).

The spelling of 31313200023221 in words is "thirty-one trillion, three hundred thirteen billion, two hundred million, twenty-three thousand, two hundred twenty-one".