312232213212221 has 2 divisors, whose sum is σ = 312232213212222. Its totient is φ = 312232213212220.

The previous prime is 312232213212217. The next prime is 312232213212223. The reversal of 312232213212221 is 122212312232213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 309328563132121 + 2903650080100 = 17587739^2 + 1704010^2 .

It is a cyclic number.

It is not a de Polignac number, because 312232213212221 - 2² = 312232213212217 is a prime.

Together with 312232213212223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (312232213212223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156116106606110 + 156116106606111.

It is an arithmetic number, because the mean of its divisors is an integer number (156116106606111).

Almost surely, 2^{312232213212221} is an apocalyptic number.

It is an amenable number.

312232213212221 is a deficient number, since it is larger than the sum of its proper divisors (1).

312232213212221 is an equidigital number, since it uses as much as digits as its factorization.

312232213212221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 29.

Adding to 312232213212221 its reverse (122212312232213), we get a palindrome (434444525444434).

The spelling of 312232213212221 in words is "three hundred twelve trillion, two hundred thirty-two billion, two hundred thirteen million, two hundred twelve thousand, two hundred twenty-one".