31210130121221 has 2 divisors, whose sum is σ = 31210130121222. Its totient is φ = 31210130121220.

The previous prime is 31210130121199. The next prime is 31210130121229. The reversal of 31210130121221 is 12212103101213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21442817548321 + 9767312572900 = 4630639^2 + 3125270^2 .

It is a cyclic number.

It is not a de Polignac number, because 31210130121221 - 2³⁸ = 30935252214277 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31210130121193 and 31210130121202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31210130121229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15605065060610 + 15605065060611.

It is an arithmetic number, because the mean of its divisors is an integer number (15605065060611).

Almost surely, 2^{31210130121221} is an apocalyptic number.

It is an amenable number.

31210130121221 is a deficient number, since it is larger than the sum of its proper divisors (1).

31210130121221 is an equidigital number, since it uses as much as digits as its factorization.

31210130121221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 20.

Adding to 31210130121221 its reverse (12212103101213), we get a palindrome (43422233222434).

The spelling of 31210130121221 in words is "thirty-one trillion, two hundred ten billion, one hundred thirty million, one hundred twenty-one thousand, two hundred twenty-one".