1331021310991 has 2 divisors, whose sum is σ = 1331021310992. Its totient is φ = 1331021310990.

The previous prime is 1331021310977. The next prime is 1331021311031. The reversal of 1331021310991 is 1990131201331.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1331021310991 - 2⁵ = 1331021310959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331021310391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 665510655495 + 665510655496.

It is an arithmetic number, because the mean of its divisors is an integer number (665510655496).

Almost surely, 2^{1331021310991} is an apocalyptic number.

1331021310991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331021310991 is an equidigital number, since it uses as much as digits as its factorization.

1331021310991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4374, while the sum is 34.

The spelling of 1331021310991 in words is "one trillion, three hundred thirty-one billion, twenty-one million, three hundred ten thousand, nine hundred ninety-one".