2665406564 has 24 divisors (see below), whose sum is σ = 4958587200. Its totient is φ = 1250056800.

The previous prime is 2665406563. The next prime is 2665406581. The reversal of 2665406564 is 4656045662.

It is a happy number.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (2665406561) 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 7 ways as a sum of consecutive naturals, for example, 165944 + ... + 181295.

It is an arithmetic number, because the mean of its divisors is an integer number (206607800).

Almost surely, 2^2665406564 is an apocalyptic number.

It is an amenable number.

2665406564 is a deficient number, since it is larger than the sum of its proper divisors (2293180636).

2665406564 is a wasteful number, since it uses less digits than its factorization.

2665406564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347363 (or 347361 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 44.

The square root of 2665406564 is about 51627.5756161375. The cubic root of 2665406564 is about 1386.5040876895.

The spelling of 2665406564 in words is "two billion, six hundred sixty-five million, four hundred six thousand, five hundred sixty-four".