256520279 has 2 divisors, whose sum is σ = 256520280. Its totient is φ = 256520278.

The previous prime is 256520267. The next prime is 256520309. The reversal of 256520279 is 972025652.

256520279 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256520279 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256520239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128260139 + 128260140.

It is an arithmetic number, because the mean of its divisors is an integer number (128260140).

Almost surely, 2^256520279 is an apocalyptic number.

256520279 is a deficient number, since it is larger than the sum of its proper divisors (1).

256520279 is an equidigital number, since it uses as much as digits as its factorization.

256520279 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 75600, while the sum is 38.

The square root of 256520279 is about 16016.2504663233. The cubic root of 256520279 is about 635.3902814984.

The spelling of 256520279 in words is "two hundred fifty-six million, five hundred twenty thousand, two hundred seventy-nine".