256666082659 has 4 divisors (see below), whose sum is σ = 293332665904. Its totient is φ = 219999499416.

The previous prime is 256666082657. The next prime is 256666082669. The reversal of 256666082659 is 956280666652.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 256666082659 - 2¹ = 256666082657 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 256666082597 and 256666082606.

It is not an unprimeable number, because it can be changed into a prime (256666082657) 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 in 3 ways as a sum of consecutive naturals, for example, 18333291612 + ... + 18333291625.

It is an arithmetic number, because the mean of its divisors is an integer number (73333166476).

Almost surely, 2^256666082659 is an apocalyptic number.

256666082659 is a deficient number, since it is larger than the sum of its proper divisors (36666583245).

256666082659 is an equidigital number, since it uses as much as digits as its factorization.

256666082659 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36666583244.

The product of its (nonzero) digits is 55987200, while the sum is 61.

The spelling of 256666082659 in words is "two hundred fifty-six billion, six hundred sixty-six million, eighty-two thousand, six hundred fifty-nine".