31130244221 has 2 divisors, whose sum is σ = 31130244222. Its totient is φ = 31130244220.

The previous prime is 31130244193. The next prime is 31130244227. The reversal of 31130244221 is 12244203113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29968456996 + 1161787225 = 173114^2 + 34085^2 .

It is an emirp because it is prime and its reverse (12244203113) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31130244221 - 2¹⁰ = 31130243197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31130244227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15565122110 + 15565122111.

It is an arithmetic number, because the mean of its divisors is an integer number (15565122111).

Almost surely, 2^31130244221 is an apocalyptic number.

It is an amenable number.

31130244221 is a deficient number, since it is larger than the sum of its proper divisors (1).

31130244221 is an equidigital number, since it uses as much as digits as its factorization.

31130244221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 31130244221 its reverse (12244203113), we get a palindrome (43374447334).

The spelling of 31130244221 in words is "thirty-one billion, one hundred thirty million, two hundred forty-four thousand, two hundred twenty-one".