2556775861 has 2 divisors, whose sum is σ = 2556775862. Its totient is φ = 2556775860.

The previous prime is 2556775853. The next prime is 2556775883. The reversal of 2556775861 is 1685776552.

2556775861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1282714225 + 1274061636 = 35815^2 + 35694^2 .

It is a cyclic number.

It is not a de Polignac number, because 2556775861 - 2³ = 2556775853 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2556775799 and 2556775808.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2556175861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1278387930 + 1278387931.

It is an arithmetic number, because the mean of its divisors is an integer number (1278387931).

Almost surely, 2^2556775861 is an apocalyptic number.

It is an amenable number.

2556775861 is a deficient number, since it is larger than the sum of its proper divisors (1).

2556775861 is an equidigital number, since it uses as much as digits as its factorization.

2556775861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3528000, while the sum is 52.

The square root of 2556775861 is about 50564.5712035611. The cubic root of 2556775861 is about 1367.4062243982.

The spelling of 2556775861 in words is "two billion, five hundred fifty-six million, seven hundred seventy-five thousand, eight hundred sixty-one".