11661165000000 has 560 divisors, whose sum is σ = 43210572779088. Its totient is φ = 3109536000000.

The previous prime is 11661164999987. The next prime is 11661165000011. The reversal of 11661165000000 is 56116611.

11661165000000 is a `hidden beast` number, since 1 + 1 + 6 + 6 + 1 + 1 + 650 + 0 + 0 + 0 + 0 + 0 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 7778877996096 + 3882287003904 = 2789064^2 + 1970352^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 404985604 + ... + 405014396.

Almost surely, 2^{11661165000000} is an apocalyptic number.

11661165000000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11661165000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21605286389544).

11661165000000 is an abundant number, since it is smaller than the sum of its proper divisors (31549407779088).

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

11661165000000 is an frugal number, since it uses more digits than its factorization.

11661165000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28852 (or 28803 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The spelling of 11661165000000 in words is "eleven trillion, six hundred sixty-one billion, one hundred sixty-five million", and thus it is an aban number.