331012391 has 2 divisors, whose sum is σ = 331012392. Its totient is φ = 331012390.

The previous prime is 331012387. The next prime is 331012417. The reversal of 331012391 is 193210133.

It is a weak prime.

It is an emirp because it is prime and its reverse (193210133) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 331012391 - 2² = 331012387 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (331012691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165506195 + 165506196.

It is an arithmetic number, because the mean of its divisors is an integer number (165506196).

Almost surely, 2^331012391 is an apocalyptic number.

331012391 is a deficient number, since it is larger than the sum of its proper divisors (1).

331012391 is an equidigital number, since it uses as much as digits as its factorization.

331012391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 486, while the sum is 23.

The square root of 331012391 is about 18193.7459309511. The cubic root of 331012391 is about 691.7482733215.

The spelling of 331012391 in words is "three hundred thirty-one million, twelve thousand, three hundred ninety-one".