2166766785 has 12 divisors (see below), whose sum is σ = 3755729172. Its totient is φ = 1155608928.

The previous prime is 2166766757. The next prime is 2166766817. The reversal of 2166766785 is 5876676612.

It can be written as a sum of positive squares in 2 ways, for example, as 843844401 + 1322922384 = 29049^2 + 36372^2 .

It is not a de Polignac number, because 2166766785 - 2⁵ = 2166766753 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24075142 + ... + 24075231.

It is an arithmetic number, because the mean of its divisors is an integer number (312977431).

Almost surely, 2^2166766785 is an apocalyptic number.

It is an amenable number.

2166766785 is a deficient number, since it is larger than the sum of its proper divisors (1588962387).

2166766785 is a wasteful number, since it uses less digits than its factorization.

2166766785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48150384 (or 48150381 counting only the distinct ones).

The product of its digits is 5080320, while the sum is 54.

The square root of 2166766785 is about 46548.5422435547. The cubic root of 2166766785 is about 1294.0092768880.

The spelling of 2166766785 in words is "two billion, one hundred sixty-six million, seven hundred sixty-six thousand, seven hundred eighty-five".