513140021 has 2 divisors, whose sum is σ = 513140022. Its totient is φ = 513140020.

The previous prime is 513140009. The next prime is 513140029. The reversal of 513140021 is 120041315.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 433680625 + 79459396 = 20825^2 + 8914^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-513140021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (513140029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 256570010 + 256570011.

It is an arithmetic number, because the mean of its divisors is an integer number (256570011).

Almost surely, 2^513140021 is an apocalyptic number.

It is an amenable number.

513140021 is a deficient number, since it is larger than the sum of its proper divisors (1).

513140021 is an equidigital number, since it uses as much as digits as its factorization.

513140021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 513140021 is about 22652.5941340059. The cubic root of 513140021 is about 800.5933207918.

Adding to 513140021 its reverse (120041315), we get a palindrome (633181336).

The spelling of 513140021 in words is "five hundred thirteen million, one hundred forty thousand, twenty-one".