31641312281 has 2 divisors, whose sum is σ = 31641312282. Its totient is φ = 31641312280.

The previous prime is 31641312251. The next prime is 31641312299. The reversal of 31641312281 is 18221314613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29816655625 + 1824656656 = 172675^2 + 42716^2 .

It is a cyclic number.

It is not a de Polignac number, because 31641312281 - 2⁶ = 31641312217 is a prime.

It is a super-2 number, since 2×31641312281² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31641312251) 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, 15820656140 + 15820656141.

It is an arithmetic number, because the mean of its divisors is an integer number (15820656141).

Almost surely, 2^31641312281 is an apocalyptic number.

It is an amenable number.

31641312281 is a deficient number, since it is larger than the sum of its proper divisors (1).

31641312281 is an equidigital number, since it uses as much as digits as its factorization.

31641312281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 32.

Adding to 31641312281 its reverse (18221314613), we get a palindrome (49862626894).

The spelling of 31641312281 in words is "thirty-one billion, six hundred forty-one million, three hundred twelve thousand, two hundred eighty-one".