304143221 has 2 divisors, whose sum is σ = 304143222. Its totient is φ = 304143220.

The previous prime is 304143199. The next prime is 304143223. The reversal of 304143221 is 122341403.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 292786321 + 11356900 = 17111^2 + 3370^2 .

It is an emirp because it is prime and its reverse (122341403) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 304143221 - 2²² = 299948917 is a prime.

Together with 304143223, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 304143193 and 304143202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (304143223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 152071610 + 152071611.

It is an arithmetic number, because the mean of its divisors is an integer number (152071611).

Almost surely, 2^304143221 is an apocalyptic number.

It is an amenable number.

304143221 is a deficient number, since it is larger than the sum of its proper divisors (1).

304143221 is an equidigital number, since it uses as much as digits as its factorization.

304143221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 304143221 is about 17439.7024343880. The cubic root of 304143221 is about 672.5006580887.

Adding to 304143221 its reverse (122341403), we get a palindrome (426484624).

The spelling of 304143221 in words is "three hundred four million, one hundred forty-three thousand, two hundred twenty-one".