166115616661 has 16 divisors (see below), whose sum is σ = 167666284800. Its totient is φ = 164573595648.

The previous prime is 166115616581. The next prime is 166115616673. The reversal of 166115616661 is 166616511661.

166115616661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 166115616661 - 2⁷ = 166115616533 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 (166115616061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58141945 + ... + 58144801.

It is an arithmetic number, because the mean of its divisors is an integer number (10479142800).

Almost surely, 2^166115616661 is an apocalyptic number.

It is an amenable number.

166115616661 is a deficient number, since it is larger than the sum of its proper divisors (1550668139).

166115616661 is a wasteful number, since it uses less digits than its factorization.

166115616661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4188.

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

The spelling of 166115616661 in words is "one hundred sixty-six billion, one hundred fifteen million, six hundred sixteen thousand, six hundred sixty-one".