304242221 has 4 divisors (see below), whose sum is σ = 304279452. Its totient is φ = 304204992.

The previous prime is 304242209. The next prime is 304242223. The reversal of 304242221 is 122242403.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 122242403 = 1307 ⋅93529.

It can be written as a sum of positive squares in 2 ways, for example, as 135606025 + 168636196 = 11645^2 + 12986^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-304242221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 304242193 and 304242202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (304242223) 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 in 3 ways as a sum of consecutive naturals, for example, 446 + ... + 24671.

It is an arithmetic number, because the mean of its divisors is an integer number (76069863).

Almost surely, 2^304242221 is an apocalyptic number.

It is an amenable number.

304242221 is a deficient number, since it is larger than the sum of its proper divisors (37231).

304242221 is a wasteful number, since it uses less digits than its factorization.

304242221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37230.

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 304242221 is about 17442.5405546325. The cubic root of 304242221 is about 672.5736175127.

Adding to 304242221 its reverse (122242403), we get a palindrome (426484624).

The spelling of 304242221 in words is "three hundred four million, two hundred forty-two thousand, two hundred twenty-one".