2564380681 has 2 divisors, whose sum is σ = 2564380682. Its totient is φ = 2564380680.

The previous prime is 2564380639. The next prime is 2564380703. The reversal of 2564380681 is 1860834652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1764000000 + 800380681 = 42000^2 + 28291^2 .

It is a cyclic number.

It is not a de Polignac number, because 2564380681 - 2¹¹ = 2564378633 is a prime.

It is a super-2 number, since 2×2564380681² = 13152096554172047522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2564380781) 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 as a sum of consecutive naturals, namely, 1282190340 + 1282190341.

It is an arithmetic number, because the mean of its divisors is an integer number (1282190341).

Almost surely, 2^2564380681 is an apocalyptic number.

It is an amenable number.

2564380681 is a deficient number, since it is larger than the sum of its proper divisors (1).

2564380681 is an equidigital number, since it uses as much as digits as its factorization.

2564380681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 276480, while the sum is 43.

The square root of 2564380681 is about 50639.7144640449. The cubic root of 2564380681 is about 1368.7606105083.

The spelling of 2564380681 in words is "two billion, five hundred sixty-four million, three hundred eighty thousand, six hundred eighty-one".