509686011297781 has 2 divisors, whose sum is σ = 509686011297782. Its totient is φ = 509686011297780.

The previous prime is 509686011297769. The next prime is 509686011297823. The reversal of 509686011297781 is 187792110686905.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 380728524454756 + 128957486843025 = 19512266^2 + 11355945^2 .

It is a cyclic number.

It is not a de Polignac number, because 509686011297781 - 2³¹ = 509683863814133 is a prime.

It is a super-2 number, since 2×509686011297781² (a number of 30 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 509686011297781.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (509686011297581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 254843005648890 + 254843005648891.

It is an arithmetic number, because the mean of its divisors is an integer number (254843005648891).

Almost surely, 2^{509686011297781} is an apocalyptic number.

It is an amenable number.

509686011297781 is a deficient number, since it is larger than the sum of its proper divisors (1).

509686011297781 is an equidigital number, since it uses as much as digits as its factorization.

509686011297781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 91445760, while the sum is 70.

The spelling of 509686011297781 in words is "five hundred nine trillion, six hundred eighty-six billion, eleven million, two hundred ninety-seven thousand, seven hundred eighty-one".