331405121 has 2 divisors, whose sum is σ = 331405122. Its totient is φ = 331405120.

The previous prime is 331405111. The next prime is 331405147. The reversal of 331405121 is 121504133.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 180606721 + 150798400 = 13439^2 + 12280^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-331405121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 331405093 and 331405102.

It is not a weakly prime, because it can be changed into another prime (331405111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165702560 + 165702561.

It is an arithmetic number, because the mean of its divisors is an integer number (165702561).

Almost surely, 2^331405121 is an apocalyptic number.

It is an amenable number.

331405121 is a deficient number, since it is larger than the sum of its proper divisors (1).

331405121 is an equidigital number, since it uses as much as digits as its factorization.

331405121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 331405121 is about 18204.5357260217. The cubic root of 331405121 is about 692.0217403541.

Adding to 331405121 its reverse (121504133), we get a palindrome (452909254).

The spelling of 331405121 in words is "three hundred thirty-one million, four hundred five thousand, one hundred twenty-one".