31303320312221 has 2 divisors, whose sum is σ = 31303320312222. Its totient is φ = 31303320312220.

The previous prime is 31303320312161. The next prime is 31303320312259. The reversal of 31303320312221 is 12221302330313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28835235324025 + 2468084988196 = 5369845^2 + 1571014^2 .

It is a cyclic number.

It is not a de Polignac number, because 31303320312221 - 2⁶ = 31303320312157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31303320392221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15651660156110 + 15651660156111.

It is an arithmetic number, because the mean of its divisors is an integer number (15651660156111).

Almost surely, 2^{31303320312221} is an apocalyptic number.

It is an amenable number.

31303320312221 is a deficient number, since it is larger than the sum of its proper divisors (1).

31303320312221 is an equidigital number, since it uses as much as digits as its factorization.

31303320312221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 26.

Adding to 31303320312221 its reverse (12221302330313), we get a palindrome (43524622642534).

The spelling of 31303320312221 in words is "thirty-one trillion, three hundred three billion, three hundred twenty million, three hundred twelve thousand, two hundred twenty-one".