2556534308257 has 2 divisors, whose sum is σ = 2556534308258. Its totient is φ = 2556534308256.

The previous prime is 2556534308249. The next prime is 2556534308269. The reversal of 2556534308257 is 7528034356552.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1306154122641 + 1250380185616 = 1142871^2 + 1118204^2 .

It is a cyclic number.

It is not a de Polignac number, because 2556534308257 - 2³ = 2556534308249 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2556534308198 and 2556534308207.

It is not a weakly prime, because it can be changed into another prime (2556534308557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1278267154128 + 1278267154129.

It is an arithmetic number, because the mean of its divisors is an integer number (1278267154129).

Almost surely, 2^{2556534308257} is an apocalyptic number.

It is an amenable number.

2556534308257 is a deficient number, since it is larger than the sum of its proper divisors (1).

2556534308257 is an equidigital number, since it uses as much as digits as its factorization.

2556534308257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240000, while the sum is 55.

The spelling of 2556534308257 in words is "two trillion, five hundred fifty-six billion, five hundred thirty-four million, three hundred eight thousand, two hundred fifty-seven".