256577 has 2 divisors, whose sum is σ = 256578. Its totient is φ = 256576.

The previous prime is 256567. The next prime is 256579. The reversal of 256577 is 775652.

It is a happy number.

256577 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 173056 + 83521 = 416^2 + 289^2 .

It is a cyclic number.

It is not a de Polignac number, because 256577 - 2⁴ = 256561 is a prime.

Together with 256579, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (256579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128288 + 128289.

It is an arithmetic number, because the mean of its divisors is an integer number (128289).

2²⁵⁶⁵⁷⁷ is an apocalyptic number.

It is an amenable number.

256577 is a deficient number, since it is larger than the sum of its proper divisors (1).

256577 is an equidigital number, since it uses as much as digits as its factorization.

256577 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14700, while the sum is 32.

The square root of 256577 is about 506.5343028858. The cubic root of 256577 is about 63.5437109916.

The spelling of 256577 in words is "two hundred fifty-six thousand, five hundred seventy-seven".