505365666109 has 2 divisors, whose sum is σ = 505365666110. Its totient is φ = 505365666108.

The previous prime is 505365666073. The next prime is 505365666131. The reversal of 505365666109 is 901666563505.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 311276958084 + 194088708025 = 557922^2 + 440555^2 .

It is a cyclic number.

It is not a de Polignac number, because 505365666109 - 2¹⁵ = 505365633341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (505365666709) 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, 252682833054 + 252682833055.

It is an arithmetic number, because the mean of its divisors is an integer number (252682833055).

Almost surely, 2^505365666109 is an apocalyptic number.

It is an amenable number.

505365666109 is a deficient number, since it is larger than the sum of its proper divisors (1).

505365666109 is an equidigital number, since it uses as much as digits as its factorization.

505365666109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4374000, while the sum is 52.

The spelling of 505365666109 in words is "five hundred five billion, three hundred sixty-five million, six hundred sixty-six thousand, one hundred nine".