256671315673 has 2 divisors, whose sum is σ = 256671315674. Its totient is φ = 256671315672.

The previous prime is 256671315671. The next prime is 256671315709. The reversal of 256671315673 is 376513176652.

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., 196287099849 + 60384215824 = 443043^2 + 245732^2 .

It is a cyclic number.

It is not a de Polignac number, because 256671315673 - 2¹ = 256671315671 is a prime.

Together with 256671315671, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 256671315673.

It is not a weakly prime, because it can be changed into another prime (256671315671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128335657836 + 128335657837.

It is an arithmetic number, because the mean of its divisors is an integer number (128335657837).

Almost surely, 2^256671315673 is an apocalyptic number.

It is an amenable number.

256671315673 is a deficient number, since it is larger than the sum of its proper divisors (1).

256671315673 is an equidigital number, since it uses as much as digits as its factorization.

256671315673 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4762800, while the sum is 52.

The spelling of 256671315673 in words is "two hundred fifty-six billion, six hundred seventy-one million, three hundred fifteen thousand, six hundred seventy-three".