256855534032389 has 2 divisors, whose sum is σ = 256855534032390. Its totient is φ = 256855534032388.

The previous prime is 256855534032341. The next prime is 256855534032407. The reversal of 256855534032389 is 983230435558652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 157985165716225 + 98870368316164 = 12569215^2 + 9943358^2 .

It is a cyclic number.

It is not a de Polignac number, because 256855534032389 - 2¹² = 256855534028293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256855534032319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128427767016194 + 128427767016195.

It is an arithmetic number, because the mean of its divisors is an integer number (128427767016195).

Almost surely, 2^{256855534032389} is an apocalyptic number.

It is an amenable number.

256855534032389 is a deficient number, since it is larger than the sum of its proper divisors (1).

256855534032389 is an equidigital number, since it uses as much as digits as its factorization.

256855534032389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 933120000, while the sum is 68.

The spelling of 256855534032389 in words is "two hundred fifty-six trillion, eight hundred fifty-five billion, five hundred thirty-four million, thirty-two thousand, three hundred eighty-nine".