11665205271 has 6 divisors (see below), whose sum is σ = 16849740960. Its totient is φ = 7776803508.

The previous prime is 11665205267. The next prime is 11665205273. The reversal of 11665205271 is 17250256611.

11665205271 is a `hidden beast` number, since 1 + 1 + 66 + 520 + 5 + 2 + 71 = 666.

It is not a de Polignac number, because 11665205271 - 2² = 11665205267 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11665205273) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 648066951 + ... + 648066968.

It is an arithmetic number, because the mean of its divisors is an integer number (2808290160).

Almost surely, 2^11665205271 is an apocalyptic number.

11665205271 is a deficient number, since it is larger than the sum of its proper divisors (5184535689).

11665205271 is a wasteful number, since it uses less digits than its factorization.

11665205271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1296133925 (or 1296133922 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 36.

The spelling of 11665205271 in words is "eleven billion, six hundred sixty-five million, two hundred five thousand, two hundred seventy-one".