304138391 has 2 divisors, whose sum is σ = 304138392. Its totient is φ = 304138390.

The previous prime is 304138379. The next prime is 304138411. The reversal of 304138391 is 193831403.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 304138391 - 2¹⁰ = 304137367 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (304138321) 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 as a sum of consecutive naturals, namely, 152069195 + 152069196.

It is an arithmetic number, because the mean of its divisors is an integer number (152069196).

Almost surely, 2^304138391 is an apocalyptic number.

304138391 is a deficient number, since it is larger than the sum of its proper divisors (1).

304138391 is an equidigital number, since it uses as much as digits as its factorization.

304138391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 304138391 is about 17439.5639567049. The cubic root of 304138391 is about 672.4970981481.

Adding to 304138391 its reverse (193831403), we get a palindrome (497969794).

The spelling of 304138391 in words is "three hundred four million, one hundred thirty-eight thousand, three hundred ninety-one".