331663393 has 2 divisors, whose sum is σ = 331663394. Its totient is φ = 331663392.

The previous prime is 331663369. The next prime is 331663403. The reversal of 331663393 is 393366133.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 251793424 + 79869969 = 15868^2 + 8937^2 .

It is a cyclic number.

It is not a de Polignac number, because 331663393 - 2⁵ = 331663361 is a prime.

It is a super-2 number, since 2×331663393² = 220001212512544898, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (331663793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165831696 + 165831697.

It is an arithmetic number, because the mean of its divisors is an integer number (165831697).

Almost surely, 2^331663393 is an apocalyptic number.

It is an amenable number.

331663393 is a deficient number, since it is larger than the sum of its proper divisors (1).

331663393 is an equidigital number, since it uses as much as digits as its factorization.

331663393 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 78732, while the sum is 37.

The square root of 331663393 is about 18211.6279612779. The cubic root of 331663393 is about 692.2014634163.

The spelling of 331663393 in words is "three hundred thirty-one million, six hundred sixty-three thousand, three hundred ninety-three".