256317936473 has 2 divisors, whose sum is σ = 256317936474. Its totient is φ = 256317936472.

The previous prime is 256317936403. The next prime is 256317936517. The reversal of 256317936473 is 374639713652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 251348814409 + 4969122064 = 501347^2 + 70492^2 .

It is a cyclic number.

It is not a de Polignac number, because 256317936473 - 2¹⁸ = 256317674329 is a prime.

It is not a weakly prime, because it can be changed into another prime (256317936403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128158968236 + 128158968237.

It is an arithmetic number, because the mean of its divisors is an integer number (128158968237).

Almost surely, 2^256317936473 is an apocalyptic number.

It is an amenable number.

256317936473 is a deficient number, since it is larger than the sum of its proper divisors (1).

256317936473 is an equidigital number, since it uses as much as digits as its factorization.

256317936473 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17146080, while the sum is 56.

The spelling of 256317936473 in words is "two hundred fifty-six billion, three hundred seventeen million, nine hundred thirty-six thousand, four hundred seventy-three".