256860839 has 2 divisors, whose sum is σ = 256860840. Its totient is φ = 256860838.

The previous prime is 256860833. The next prime is 256860869. The reversal of 256860839 is 938068652.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256860839 is a prime.

It is a super-2 number, since 2×256860839² = 131954981223567842, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 256860793 and 256860802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256860833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128430419 + 128430420.

It is an arithmetic number, because the mean of its divisors is an integer number (128430420).

Almost surely, 2^256860839 is an apocalyptic number.

256860839 is a deficient number, since it is larger than the sum of its proper divisors (1).

256860839 is an equidigital number, since it uses as much as digits as its factorization.

256860839 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 622080, while the sum is 47.

The square root of 256860839 is about 16026.8786418317. The cubic root of 256860839 is about 635.6713415710.

The spelling of 256860839 in words is "two hundred fifty-six million, eight hundred sixty thousand, eight hundred thirty-nine".