256786559999 has 2 divisors, whose sum is σ = 256786560000. Its totient is φ = 256786559998.

The previous prime is 256786559977. The next prime is 256786560001. The reversal of 256786559999 is 999955687652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256786559999 - 2³⁶ = 188067083263 is a prime.

It is a super-2 number, since 2×256786559999² (a number of 24 digits) contains 22 as substring.

Together with 256786560001, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256786552999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128393279999 + 128393280000.

It is an arithmetic number, because the mean of its divisors is an integer number (128393280000).

Almost surely, 2^256786559999 is an apocalyptic number.

256786559999 is a deficient number, since it is larger than the sum of its proper divisors (1).

256786559999 is an equidigital number, since it uses as much as digits as its factorization.

256786559999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3306744000, while the sum is 80.

The spelling of 256786559999 in words is "two hundred fifty-six billion, seven hundred eighty-six million, five hundred fifty-nine thousand, nine hundred ninety-nine".