331009121 has 2 divisors, whose sum is σ = 331009122. Its totient is φ = 331009120.

The previous prime is 331009111. The next prime is 331009177. The reversal of 331009121 is 121900133.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 308494096 + 22515025 = 17564^2 + 4745^2 .

It is an emirp because it is prime and its reverse (121900133) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-331009121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 331009093 and 331009102.

It is not a weakly prime, because it can be changed into another prime (331009111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165504560 + 165504561.

It is an arithmetic number, because the mean of its divisors is an integer number (165504561).

Almost surely, 2^331009121 is an apocalyptic number.

It is an amenable number.

331009121 is a deficient number, since it is larger than the sum of its proper divisors (1).

331009121 is an equidigital number, since it uses as much as digits as its factorization.

331009121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162, while the sum is 20.

The square root of 331009121 is about 18193.6560646836. The cubic root of 331009121 is about 691.7459954367.

Adding to 331009121 its reverse (121900133), we get a palindrome (452909254).

The spelling of 331009121 in words is "three hundred thirty-one million, nine thousand, one hundred twenty-one".