2556540065 has 16 divisors (see below), whose sum is σ = 3141504000. Its totient is φ = 1996517952.

The previous prime is 2556540047. The next prime is 2556540067. The reversal of 2556540065 is 5600456552.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2556540065 - 2¹⁸ = 2556277921 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2556540067) 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 15 ways as a sum of consecutive naturals, for example, 28496 + ... + 76974.

It is an arithmetic number, because the mean of its divisors is an integer number (196344000).

Almost surely, 2^2556540065 is an apocalyptic number.

It is an amenable number.

2556540065 is a deficient number, since it is larger than the sum of its proper divisors (584963935).

2556540065 is a wasteful number, since it uses less digits than its factorization.

2556540065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48736.

The product of its (nonzero) digits is 180000, while the sum is 38.

The square root of 2556540065 is about 50562.2395172524. The cubic root of 2556540065 is about 1367.3641872326.

The spelling of 2556540065 in words is "two billion, five hundred fifty-six million, five hundred forty thousand, sixty-five".