11666561516011 has 4 divisors (see below), whose sum is σ = 11666596723272. Its totient is φ = 11666526308752.

The previous prime is 11666561515997. The next prime is 11666561516023. The reversal of 11666561516011 is 11061516566611.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 11666561516011 - 2⁵ = 11666561515979 is a prime.

It is a super-2 number, since 2×11666561516011² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11666561616011) 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, 17101810 + ... + 17770903.

It is an arithmetic number, because the mean of its divisors is an integer number (2916649180818).

Almost surely, 2^{11666561516011} is an apocalyptic number.

11666561516011 is a deficient number, since it is larger than the sum of its proper divisors (35207261).

11666561516011 is an equidigital number, since it uses as much as digits as its factorization.

11666561516011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35207260.

The product of its (nonzero) digits is 194400, while the sum is 46.

The spelling of 11666561516011 in words is "eleven trillion, six hundred sixty-six billion, five hundred sixty-one million, five hundred sixteen thousand, eleven".