2165713866 has 24 divisors (see below), whose sum is σ = 4769306724. Its totient is φ = 710069760.

The previous prime is 2165713853. The next prime is 2165713867. The reversal of 2165713866 is 6683175612.

2165713866 is a `hidden beast` number, since 2 + 16 + 571 + 3 + 8 + 66 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1942958241 + 222755625 = 44079^2 + 14925^2 .

It is not an unprimeable number, because it can be changed into a prime (2165713867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 985111 + ... + 987306.

Almost surely, 2^2165713866 is an apocalyptic number.

2165713866 is an abundant number, since it is smaller than the sum of its proper divisors (2603592858).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2165713866 is a wasteful number, since it uses less digits than its factorization.

2165713866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1972486 (or 1972483 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 2165713866 is about 46537.2309661845. The cubic root of 2165713866 is about 1293.7996392352.

The spelling of 2165713866 in words is "two billion, one hundred sixty-five million, seven hundred thirteen thousand, eight hundred sixty-six".