331991890013909 has 2 divisors, whose sum is σ = 331991890013910. Its totient is φ = 331991890013908.

The previous prime is 331991890013887. The next prime is 331991890013977. The reversal of 331991890013909 is 909310098199133.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 269304608713009 + 62687281300900 = 16410503^2 + 7917530^2 .

It is a cyclic number.

It is not a de Polignac number, because 331991890013909 - 2⁸ = 331991890013653 is a prime.

It is a super-2 number, since 2×331991890013909² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (331991890013999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165995945006954 + 165995945006955.

It is an arithmetic number, because the mean of its divisors is an integer number (165995945006955).

Almost surely, 2^{331991890013909} is an apocalyptic number.

It is an amenable number.

331991890013909 is a deficient number, since it is larger than the sum of its proper divisors (1).

331991890013909 is an equidigital number, since it uses as much as digits as its factorization.

331991890013909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12754584, while the sum is 65.

The spelling of 331991890013909 in words is "three hundred thirty-one trillion, nine hundred ninety-one billion, eight hundred ninety million, thirteen thousand, nine hundred nine".