166871605841 has 2 divisors, whose sum is σ = 166871605842. Its totient is φ = 166871605840.

The previous prime is 166871605783. The next prime is 166871605883. The reversal of 166871605841 is 148506178661.

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., 116471355841 + 50400250000 = 341279^2 + 224500^2 .

It is a cyclic number.

It is not a de Polignac number, because 166871605841 - 2⁶ = 166871605777 is a prime.

It is a super-2 number, since 2×166871605841² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (166871695841) 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, 83435802920 + 83435802921.

It is an arithmetic number, because the mean of its divisors is an integer number (83435802921).

Almost surely, 2^166871605841 is an apocalyptic number.

It is an amenable number.

166871605841 is a deficient number, since it is larger than the sum of its proper divisors (1).

166871605841 is an equidigital number, since it uses as much as digits as its factorization.

166871605841 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1935360, while the sum is 53.

The spelling of 166871605841 in words is "one hundred sixty-six billion, eight hundred seventy-one million, six hundred five thousand, eight hundred forty-one".