256862591 has 2 divisors, whose sum is σ = 256862592. Its totient is φ = 256862590.

The previous prime is 256862579. The next prime is 256862603. The reversal of 256862591 is 195268652.

It is a balanced prime because it is at equal distance from previous prime (256862579) and next prime (256862603).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256862591 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256862561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128431295 + 128431296.

It is an arithmetic number, because the mean of its divisors is an integer number (128431296).

Almost surely, 2^256862591 is an apocalyptic number.

256862591 is a deficient number, since it is larger than the sum of its proper divisors (1).

256862591 is an equidigital number, since it uses as much as digits as its factorization.

256862591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 259200, while the sum is 44.

The square root of 256862591 is about 16026.9332999174. The cubic root of 256862591 is about 635.6727868330.

The spelling of 256862591 in words is "two hundred fifty-six million, eight hundred sixty-two thousand, five hundred ninety-one".