1304431021 has 2 divisors, whose sum is σ = 1304431022. Its totient is φ = 1304431020.

The previous prime is 1304431003. The next prime is 1304431033. The reversal of 1304431021 is 1201344031.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 955675396 + 348755625 = 30914^2 + 18675^2 .

It is a cyclic number.

It is not a de Polignac number, because 1304431021 - 2⁹ = 1304430509 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1304431021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1304431421) 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 as a sum of consecutive naturals, namely, 652215510 + 652215511.

It is an arithmetic number, because the mean of its divisors is an integer number (652215511).

Almost surely, 2^1304431021 is an apocalyptic number.

It is an amenable number.

1304431021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1304431021 is an equidigital number, since it uses as much as digits as its factorization.

1304431021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 1304431021 is about 36116.9076887820. The cubic root of 1304431021 is about 1092.6314729883.

Adding to 1304431021 its reverse (1201344031), we get a palindrome (2505775052).

The spelling of 1304431021 in words is "one billion, three hundred four million, four hundred thirty-one thousand, twenty-one".