211671660165 has 16 divisors (see below), whose sum is σ = 387056750208. Its totient is φ = 96764187456.

The previous prime is 211671660149. The next prime is 211671660199. The reversal of 211671660165 is 561066176112.

It is a happy number.

It is not a de Polignac number, because 211671660165 - 2⁴ = 211671660149 is a prime.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 1007960182 + ... + 1007960391.

It is an arithmetic number, because the mean of its divisors is an integer number (24191046888).

Almost surely, 2^211671660165 is an apocalyptic number.

It is an amenable number.

211671660165 is a deficient number, since it is larger than the sum of its proper divisors (175385090043).

211671660165 is a wasteful number, since it uses less digits than its factorization.

211671660165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2015920588.

The product of its (nonzero) digits is 90720, while the sum is 42.

The spelling of 211671660165 in words is "two hundred eleven billion, six hundred seventy-one million, six hundred sixty thousand, one hundred sixty-five".