256511587 has 2 divisors, whose sum is σ = 256511588. Its totient is φ = 256511586.

The previous prime is 256511579. The next prime is 256511611. The reversal of 256511587 is 785115652.

It is a happy number.

256511587 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 not a de Polignac number, because 256511587 - 2³ = 256511579 is a prime.

It is not a weakly prime, because it can be changed into another prime (256511537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128255793 + 128255794.

It is an arithmetic number, because the mean of its divisors is an integer number (128255794).

Almost surely, 2^256511587 is an apocalyptic number.

256511587 is a deficient number, since it is larger than the sum of its proper divisors (1).

256511587 is an equidigital number, since it uses as much as digits as its factorization.

256511587 is an evil number, because the sum of its binary digits is even.

The product of its digits is 84000, while the sum is 40.

The square root of 256511587 is about 16015.9791146217. The cubic root of 256511587 is about 635.3831048407.

The spelling of 256511587 in words is "two hundred fifty-six million, five hundred eleven thousand, five hundred eighty-seven".