2564811555 has 16 divisors (see below), whose sum is σ = 4123152384. Its totient is φ = 1361414880.

The previous prime is 2564811553. The next prime is 2564811589. The reversal of 2564811555 is 5551184652.

It is not a de Polignac number, because 2564811555 - 2¹ = 2564811553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2564811553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 402019 + ... + 408348.

It is an arithmetic number, because the mean of its divisors is an integer number (257697024).

Almost surely, 2^2564811555 is an apocalyptic number.

2564811555 is a deficient number, since it is larger than the sum of its proper divisors (1558340829).

2564811555 is a wasteful number, since it uses less digits than its factorization.

2564811555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810586.

The product of its digits is 240000, while the sum is 42.

The square root of 2564811555 is about 50643.9685944931. The cubic root of 2564811555 is about 1368.8372671367.

The spelling of 2564811555 in words is "two billion, five hundred sixty-four million, eight hundred eleven thousand, five hundred fifty-five".