518205397 has 2 divisors, whose sum is σ = 518205398. Its totient is φ = 518205396.

The previous prime is 518205283. The next prime is 518205419. The reversal of 518205397 is 793502815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 344993476 + 173211921 = 18574^2 + 13161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-518205397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (518209397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 259102698 + 259102699.

It is an arithmetic number, because the mean of its divisors is an integer number (259102699).

Almost surely, 2^518205397 is an apocalyptic number.

It is an amenable number.

518205397 is a deficient number, since it is larger than the sum of its proper divisors (1).

518205397 is an equidigital number, since it uses as much as digits as its factorization.

518205397 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 75600, while the sum is 40.

The square root of 518205397 is about 22764.1252193007. The cubic root of 518205397 is about 803.2190077182.

The spelling of 518205397 in words is "five hundred eighteen million, two hundred five thousand, three hundred ninety-seven".