256542708997 has 2 divisors, whose sum is σ = 256542708998. Its totient is φ = 256542708996.

The previous prime is 256542708959. The next prime is 256542709001. The reversal of 256542708997 is 799807245652.

256542708997 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., 224045075556 + 32497633441 = 473334^2 + 180271^2 .

It is a cyclic number.

It is not a de Polignac number, because 256542708997 - 2¹⁹ = 256542184709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256542705997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128271354498 + 128271354499.

It is an arithmetic number, because the mean of its divisors is an integer number (128271354499).

Almost surely, 2^256542708997 is an apocalyptic number.

It is an amenable number.

256542708997 is a deficient number, since it is larger than the sum of its proper divisors (1).

256542708997 is an equidigital number, since it uses as much as digits as its factorization.

256542708997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 76204800, while the sum is 64.

The spelling of 256542708997 in words is "two hundred fifty-six billion, five hundred forty-two million, seven hundred eight thousand, nine hundred ninety-seven".