11661165006661 has 4 divisors (see below), whose sum is σ = 11693647360800. Its totient is φ = 11628682652524.

The previous prime is 11661165006649. The next prime is 11661165006677. The reversal of 11661165006661 is 16660056116611.

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 11661165006661 - 2¹⁵ = 11661164973893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11661165006061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16241176531 + ... + 16241177248.

It is an arithmetic number, because the mean of its divisors is an integer number (2923411840200).

Almost surely, 2^{11661165006661} is an apocalyptic number.

It is an amenable number.

11661165006661 is a deficient number, since it is larger than the sum of its proper divisors (32482354139).

11661165006661 is an equidigital number, since it uses as much as digits as its factorization.

11661165006661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32482354138.

The product of its (nonzero) digits is 233280, while the sum is 46.

The spelling of 11661165006661 in words is "eleven trillion, six hundred sixty-one billion, one hundred sixty-five million, six thousand, six hundred sixty-one".