304542221 has 2 divisors, whose sum is σ = 304542222. Its totient is φ = 304542220.

The previous prime is 304542209. The next prime is 304542239. The reversal of 304542221 is 122245403.

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., 278389225 + 26152996 = 16685^2 + 5114^2 .

It is a cyclic number.

It is not a de Polignac number, because 304542221 - 2⁶ = 304542157 is a prime.

It is a super-2 number, since 2×304542221² = 185491928743225682, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (304592221) 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, 152271110 + 152271111.

It is an arithmetic number, because the mean of its divisors is an integer number (152271111).

Almost surely, 2^304542221 is an apocalyptic number.

It is an amenable number.

304542221 is a deficient number, since it is larger than the sum of its proper divisors (1).

304542221 is an equidigital number, since it uses as much as digits as its factorization.

304542221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 304542221 is about 17451.1381004220. The cubic root of 304542221 is about 672.7946100729.

Adding to 304542221 its reverse (122245403), we get a palindrome (426787624).

The spelling of 304542221 in words is "three hundred four million, five hundred forty-two thousand, two hundred twenty-one".