506166565991 has 2 divisors, whose sum is σ = 506166565992. Its totient is φ = 506166565990.

The previous prime is 506166565969. The next prime is 506166566029. The reversal of 506166565991 is 199565661605.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 506166565991 - 2³⁸ = 231288659047 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 506166565991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (506166565291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 253083282995 + 253083282996.

It is an arithmetic number, because the mean of its divisors is an integer number (253083282996).

Almost surely, 2^506166565991 is an apocalyptic number.

506166565991 is a deficient number, since it is larger than the sum of its proper divisors (1).

506166565991 is an equidigital number, since it uses as much as digits as its factorization.

506166565991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13122000, while the sum is 59.

The spelling of 506166565991 in words is "five hundred six billion, one hundred sixty-six million, five hundred sixty-five thousand, nine hundred ninety-one".