304228721 has 4 divisors (see below), whose sum is σ = 309385200. Its totient is φ = 299072244.

The previous prime is 304228693. The next prime is 304228723. The reversal of 304228721 is 127822403.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 127822403 = 487 ⋅262469.

It is a cyclic number.

It is not a de Polignac number, because 304228721 - 2¹⁸ = 303966577 is a prime.

It is a super-2 number, since 2×304228721² = 185110229362591682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (304228723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2578151 + ... + 2578268.

It is an arithmetic number, because the mean of its divisors is an integer number (77346300).

Almost surely, 2^304228721 is an apocalyptic number.

It is an amenable number.

304228721 is a deficient number, since it is larger than the sum of its proper divisors (5156479).

304228721 is an equidigital number, since it uses as much as digits as its factorization.

304228721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5156478.

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 304228721 is about 17442.1535654288. The cubic root of 304228721 is about 672.5636694324.

The spelling of 304228721 in words is "three hundred four million, two hundred twenty-eight thousand, seven hundred twenty-one".