2556055681 has 2 divisors, whose sum is σ = 2556055682. Its totient is φ = 2556055680.

The previous prime is 2556055673. The next prime is 2556055729. The reversal of 2556055681 is 1865506552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2070250000 + 485805681 = 45500^2 + 22041^2 .

It is a cyclic number.

It is not a de Polignac number, because 2556055681 - 2³ = 2556055673 is a prime.

It is a super-2 number, since 2×2556055681² = 13066841288744747522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2556055631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1278027840 + 1278027841.

It is an arithmetic number, because the mean of its divisors is an integer number (1278027841).

Almost surely, 2^2556055681 is an apocalyptic number.

It is an amenable number.

2556055681 is a deficient number, since it is larger than the sum of its proper divisors (1).

2556055681 is an equidigital number, since it uses as much as digits as its factorization.

2556055681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360000, while the sum is 43.

The square root of 2556055681 is about 50557.4493126384. The cubic root of 2556055681 is about 1367.2778242639.

The spelling of 2556055681 in words is "two billion, five hundred fifty-six million, fifty-five thousand, six hundred eighty-one".