2565461665 has 8 divisors (see below), whose sum is σ = 3315365928. Its totient is φ = 1894494720.

The previous prime is 2565461651. The next prime is 2565461683. The reversal of 2565461665 is 5661645652.

2565461665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 4393216 + 2561068449 = 2096^2 + 50607^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2565461665 - 2⁷ = 2565461537 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19734256 + ... + 19734385.

It is an arithmetic number, because the mean of its divisors is an integer number (414420741).

Almost surely, 2^2565461665 is an apocalyptic number.

It is an amenable number.

2565461665 is a deficient number, since it is larger than the sum of its proper divisors (749904263).

2565461665 is a wasteful number, since it uses less digits than its factorization.

2565461665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39468659.

The product of its digits is 1296000, while the sum is 46.

The square root of 2565461665 is about 50650.3866224139. The cubic root of 2565461665 is about 1368.9529117106.

The spelling of 2565461665 in words is "two billion, five hundred sixty-five million, four hundred sixty-one thousand, six hundred sixty-five".