331020161 has 2 divisors, whose sum is σ = 331020162. Its totient is φ = 331020160.

The previous prime is 331020119. The next prime is 331020169. The reversal of 331020161 is 161020133.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 208253761 + 122766400 = 14431^2 + 11080^2 .

It is an emirp because it is prime and its reverse (161020133) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 331020161 - 2⁶ = 331020097 is a prime.

It is not a weakly prime, because it can be changed into another prime (331020169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165510080 + 165510081.

It is an arithmetic number, because the mean of its divisors is an integer number (165510081).

Almost surely, 2^331020161 is an apocalyptic number.

It is an amenable number.

331020161 is a deficient number, since it is larger than the sum of its proper divisors (1).

331020161 is an equidigital number, since it uses as much as digits as its factorization.

331020161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 331020161 is about 18193.9594646135. The cubic root of 331020161 is about 691.7536858500.

Adding to 331020161 its reverse (161020133), we get a palindrome (492040294).

The spelling of 331020161 in words is "three hundred thirty-one million, twenty thousand, one hundred sixty-one".