3131002331221 has 2 divisors, whose sum is σ = 3131002331222. Its totient is φ = 3131002331220.

The previous prime is 3131002331207. The next prime is 3131002331263. The reversal of 3131002331221 is 1221332001313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1731250692900 + 1399751638321 = 1315770^2 + 1183111^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3131002331221 is a prime.

It is a super-2 number, since 2×3131002331221² (a number of 26 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 3131002331192 and 3131002331201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3131002331521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1565501165610 + 1565501165611.

It is an arithmetic number, because the mean of its divisors is an integer number (1565501165611).

Almost surely, 2^{3131002331221} is an apocalyptic number.

It is an amenable number.

3131002331221 is a deficient number, since it is larger than the sum of its proper divisors (1).

3131002331221 is an equidigital number, since it uses as much as digits as its factorization.

3131002331221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 22.

Adding to 3131002331221 its reverse (1221332001313), we get a palindrome (4352334332534).

The spelling of 3131002331221 in words is "three trillion, one hundred thirty-one billion, two million, three hundred thirty-one thousand, two hundred twenty-one".