2556404520281 has 2 divisors, whose sum is σ = 2556404520282. Its totient is φ = 2556404520280.

The previous prime is 2556404520169. The next prime is 2556404520287. The reversal of 2556404520281 is 1820254046552.

2556404520281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1735387310281 + 821017210000 = 1317341^2 + 906100^2 .

It is a cyclic number.

It is not a de Polignac number, because 2556404520281 - 2¹⁴ = 2556404503897 is a prime.

It is a super-2 number, since 2×2556404520281² (a number of 26 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2556404520287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1278202260140 + 1278202260141.

It is an arithmetic number, because the mean of its divisors is an integer number (1278202260141).

Almost surely, 2^{2556404520281} is an apocalyptic number.

It is an amenable number.

2556404520281 is a deficient number, since it is larger than the sum of its proper divisors (1).

2556404520281 is an equidigital number, since it uses as much as digits as its factorization.

2556404520281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 768000, while the sum is 44.

The spelling of 2556404520281 in words is "two trillion, five hundred fifty-six billion, four hundred four million, five hundred twenty thousand, two hundred eighty-one".