131666500166681 has 4 divisors (see below), whose sum is σ = 131671149600000. Its totient is φ = 131661850733364.

The previous prime is 131666500166657. The next prime is 131666500166701. The reversal of 131666500166681 is 186661005666131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 131666500166681 - 2³⁴ = 131649320297497 is a prime.

It is a super-2 number, since 2×131666500166681² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131666500160681) 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 in 3 ways as a sum of consecutive naturals, for example, 2324674181 + ... + 2324730818.

It is an arithmetic number, because the mean of its divisors is an integer number (32917787400000).

Almost surely, 2^{131666500166681} is an apocalyptic number.

It is an amenable number.

131666500166681 is a deficient number, since it is larger than the sum of its proper divisors (4649433319).

131666500166681 is an equidigital number, since it uses as much as digits as its factorization.

131666500166681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4649433318.

The product of its (nonzero) digits is 5598720, while the sum is 56.

The spelling of 131666500166681 in words is "one hundred thirty-one trillion, six hundred sixty-six billion, five hundred million, one hundred sixty-six thousand, six hundred eighty-one".