331131220081 has 2 divisors, whose sum is σ = 331131220082. Its totient is φ = 331131220080.

The previous prime is 331131220073. The next prime is 331131220181. The reversal of 331131220081 is 180022131133.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 222505607025 + 108625613056 = 471705^2 + 329584^2 .

It is a cyclic number.

It is not a de Polignac number, because 331131220081 - 2³ = 331131220073 is a prime.

It is a super-2 number, since 2×331131220081² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (331131220001) 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, 165565610040 + 165565610041.

It is an arithmetic number, because the mean of its divisors is an integer number (165565610041).

Almost surely, 2^331131220081 is an apocalyptic number.

It is an amenable number.

331131220081 is a deficient number, since it is larger than the sum of its proper divisors (1).

331131220081 is an equidigital number, since it uses as much as digits as its factorization.

331131220081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 25.

The spelling of 331131220081 in words is "three hundred thirty-one billion, one hundred thirty-one million, two hundred twenty thousand, eighty-one".