331013021 has 2 divisors, whose sum is σ = 331013022. Its totient is φ = 331013020.

The previous prime is 331013017. The next prime is 331013077. The reversal of 331013021 is 120310133.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 324180025 + 6832996 = 18005^2 + 2614^2 .

It is a cyclic number.

It is not a de Polignac number, because 331013021 - 2² = 331013017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 331012987 and 331013005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (331013821) 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, 165506510 + 165506511.

It is an arithmetic number, because the mean of its divisors is an integer number (165506511).

Almost surely, 2^331013021 is an apocalyptic number.

It is an amenable number.

331013021 is a deficient number, since it is larger than the sum of its proper divisors (1).

331013021 is an equidigital number, since it uses as much as digits as its factorization.

331013021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54, while the sum is 14.

The square root of 331013021 is about 18193.7632445847. The cubic root of 331013021 is about 691.7487121783.

Adding to 331013021 its reverse (120310133), we get a palindrome (451323154).

The spelling of 331013021 in words is "three hundred thirty-one million, thirteen thousand, twenty-one".