11115161661 has 4 divisors (see below), whose sum is σ = 14820215552. Its totient is φ = 7410107772.

The previous prime is 11115161641. The next prime is 11115161737. The reversal of 11115161661 is 16616151111.

11115161661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 not a de Polignac number, because 11115161661 - 2⁹ = 11115161149 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 (11115161621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1852526941 + ... + 1852526946.

It is an arithmetic number, because the mean of its divisors is an integer number (3705053888).

Almost surely, 2^11115161661 is an apocalyptic number.

It is an amenable number.

11115161661 is a deficient number, since it is larger than the sum of its proper divisors (3705053891).

11115161661 is an equidigital number, since it uses as much as digits as its factorization.

11115161661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3705053890.

The product of its digits is 1080, while the sum is 30.

The spelling of 11115161661 in words is "eleven billion, one hundred fifteen million, one hundred sixty-one thousand, six hundred sixty-one".