166531444405049 has 2 divisors, whose sum is σ = 166531444405050. Its totient is φ = 166531444405048.

The previous prime is 166531444404979. The next prime is 166531444405063. The reversal of 166531444405049 is 940504444135661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 166423725883024 + 107718522025 = 12900532^2 + 328205^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166531444405049 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166531444404985 and 166531444405003.

It is not a weakly prime, because it can be changed into another prime (166531444455049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83265722202524 + 83265722202525.

It is an arithmetic number, because the mean of its divisors is an integer number (83265722202525).

Almost surely, 2^{166531444405049} is an apocalyptic number.

It is an amenable number.

166531444405049 is a deficient number, since it is larger than the sum of its proper divisors (1).

166531444405049 is an equidigital number, since it uses as much as digits as its factorization.

166531444405049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24883200, while the sum is 56.

The spelling of 166531444405049 in words is "one hundred sixty-six trillion, five hundred thirty-one billion, four hundred forty-four million, four hundred five thousand, forty-nine".