11665205821212 has 12 divisors (see below), whose sum is σ = 27218813582856. Its totient is φ = 3888401940400.

The previous prime is 11665205821177. The next prime is 11665205821229. The reversal of 11665205821212 is 21212850256611.

11665205821212 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 486050242539 + ... + 486050242562.

It is an arithmetic number, because the mean of its divisors is an integer number (2268234465238).

Almost surely, 2^{11665205821212} is an apocalyptic number.

11665205821212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

11665205821212 is an abundant number, since it is smaller than the sum of its proper divisors (15553607761644).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11665205821212 is a wasteful number, since it uses less digits than its factorization.

11665205821212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 972100485108 (or 972100485106 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 42.

The spelling of 11665205821212 in words is "eleven trillion, six hundred sixty-five billion, two hundred five million, eight hundred twenty-one thousand, two hundred twelve".