11515516561011 has 4 divisors (see below), whose sum is σ = 15354022081352. Its totient is φ = 7677011040672.

The previous prime is 11515516561007. The next prime is 11515516561013. The reversal of 11515516561011 is 11016561551511.

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

It is not a de Polignac number, because 11515516561011 - 2² = 11515516561007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11515516561013) 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, 1919252760166 + ... + 1919252760171.

It is an arithmetic number, because the mean of its divisors is an integer number (3838505520338).

Almost surely, 2^{11515516561011} is an apocalyptic number.

11515516561011 is a deficient number, since it is larger than the sum of its proper divisors (3838505520341).

11515516561011 is an equidigital number, since it uses as much as digits as its factorization.

11515516561011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3838505520340.

The product of its (nonzero) digits is 22500, while the sum is 39.

The spelling of 11515516561011 in words is "eleven trillion, five hundred fifteen billion, five hundred sixteen million, five hundred sixty-one thousand, eleven".