518417993 has 2 divisors, whose sum is σ = 518417994. Its totient is φ = 518417992.

The previous prime is 518417923. The next prime is 518418023. The reversal of 518417993 is 399714815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 473367049 + 45050944 = 21757^2 + 6712^2 .

It is a cyclic number.

It is not a de Polignac number, because 518417993 - 2¹⁸ = 518155849 is a prime.

It is a super-2 number, since 2×518417993² = 537514430932296098, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (518417903) 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, 259208996 + 259208997.

It is an arithmetic number, because the mean of its divisors is an integer number (259208997).

Almost surely, 2^518417993 is an apocalyptic number.

It is an amenable number.

518417993 is a deficient number, since it is larger than the sum of its proper divisors (1).

518417993 is an equidigital number, since it uses as much as digits as its factorization.

518417993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 272160, while the sum is 47.

The square root of 518417993 is about 22768.7942807695. The cubic root of 518417993 is about 803.3288340552.

The spelling of 518417993 in words is "five hundred eighteen million, four hundred seventeen thousand, nine hundred ninety-three".