304021321 has 2 divisors, whose sum is σ = 304021322. Its totient is φ = 304021320.

The previous prime is 304021313. The next prime is 304021357. The reversal of 304021321 is 123120403.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 304014096 + 7225 = 17436^2 + 85^2 .

It is a cyclic number.

It is not a de Polignac number, because 304021321 - 2³ = 304021313 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 304021295 and 304021304.

It is not a weakly prime, because it can be changed into another prime (304021021) 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, 152010660 + 152010661.

It is an arithmetic number, because the mean of its divisors is an integer number (152010661).

Almost surely, 2^304021321 is an apocalyptic number.

It is an amenable number.

304021321 is a deficient number, since it is larger than the sum of its proper divisors (1).

304021321 is an equidigital number, since it uses as much as digits as its factorization.

304021321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 304021321 is about 17436.2071850503. The cubic root of 304021321 is about 672.4108004392.

Adding to 304021321 its reverse (123120403), we get a palindrome (427141724).

The spelling of 304021321 in words is "three hundred four million, twenty-one thousand, three hundred twenty-one".