304405021 has 2 divisors, whose sum is σ = 304405022. Its totient is φ = 304405020.

The previous prime is 304405007. The next prime is 304405039. The reversal of 304405021 is 120504403.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 271755225 + 32649796 = 16485^2 + 5714^2 .

It is a cyclic number.

It is not a de Polignac number, because 304405021 - 2⁹ = 304404509 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 304405021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (304405051) 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, 152202510 + 152202511.

It is an arithmetic number, because the mean of its divisors is an integer number (152202511).

Almost surely, 2^304405021 is an apocalyptic number.

It is an amenable number.

304405021 is a deficient number, since it is larger than the sum of its proper divisors (1).

304405021 is an equidigital number, since it uses as much as digits as its factorization.

304405021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 304405021 is about 17447.2066818732. The cubic root of 304405021 is about 672.6935608264.

Adding to 304405021 its reverse (120504403), we get a palindrome (424909424).

The spelling of 304405021 in words is "three hundred four million, four hundred five thousand, twenty-one".