256515999071 has 2 divisors, whose sum is σ = 256515999072. Its totient is φ = 256515999070.

The previous prime is 256515999053. The next prime is 256515999107. The reversal of 256515999071 is 170999515652.

It is a happy number.

Together with next prime (256515999107) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 256515999071 - 2²² = 256511804767 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 256515999071.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256515999041) 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, 128257999535 + 128257999536.

It is an arithmetic number, because the mean of its divisors is an integer number (128257999536).

Almost surely, 2^256515999071 is an apocalyptic number.

256515999071 is a deficient number, since it is larger than the sum of its proper divisors (1).

256515999071 is an equidigital number, since it uses as much as digits as its factorization.

256515999071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7654500, while the sum is 59.

The spelling of 256515999071 in words is "two hundred fifty-six billion, five hundred fifteen million, nine hundred ninety-nine thousand, seventy-one".