304216421 has 2 divisors, whose sum is σ = 304216422. Its totient is φ = 304216420.

The previous prime is 304216417. The next prime is 304216447. The reversal of 304216421 is 124612403.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 291931396 + 12285025 = 17086^2 + 3505^2 .

It is a cyclic number.

It is not a de Polignac number, because 304216421 - 2² = 304216417 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (304216481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 152108210 + 152108211.

It is an arithmetic number, because the mean of its divisors is an integer number (152108211).

Almost surely, 2^304216421 is an apocalyptic number.

It is an amenable number.

304216421 is a deficient number, since it is larger than the sum of its proper divisors (1).

304216421 is an equidigital number, since it uses as much as digits as its factorization.

304216421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 304216421 is about 17441.8009677900. The cubic root of 304216421 is about 672.5546053697.

Adding to 304216421 its reverse (124612403), we get a palindrome (428828824).

The spelling of 304216421 in words is "three hundred four million, two hundred sixteen thousand, four hundred twenty-one".