2564276665 has 4 divisors (see below), whose sum is σ = 3077132004. Its totient is φ = 2051421328.

The previous prime is 2564276609. The next prime is 2564276677. The reversal of 2564276665 is 5666724652.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 624050361 + 1940226304 = 24981^2 + 44048^2 .

It is a cyclic number.

It is not a de Polignac number, because 2564276665 - 2¹¹ = 2564274617 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 256427662 + ... + 256427671.

It is an arithmetic number, because the mean of its divisors is an integer number (769283001).

Almost surely, 2^2564276665 is an apocalyptic number.

It is an amenable number.

2564276665 is a deficient number, since it is larger than the sum of its proper divisors (512855339).

2564276665 is an equidigital number, since it uses as much as digits as its factorization.

2564276665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512855338.

The product of its digits is 3628800, while the sum is 49.

The square root of 2564276665 is about 50638.6874336213. The cubic root of 2564276665 is about 1368.7421037749.

The spelling of 2564276665 in words is "two billion, five hundred sixty-four million, two hundred seventy-six thousand, six hundred sixty-five".