256641311 has 2 divisors, whose sum is σ = 256641312. Its totient is φ = 256641310.

The previous prime is 256641277. The next prime is 256641323. The reversal of 256641311 is 113146652.

It is a happy number.

256641311 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 is a cyclic number.

It is not a de Polignac number, because 256641311 - 2⁶ = 256641247 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 (256641391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128320655 + 128320656.

It is an arithmetic number, because the mean of its divisors is an integer number (128320656).

Almost surely, 2^256641311 is an apocalyptic number.

256641311 is a deficient number, since it is larger than the sum of its proper divisors (1).

256641311 is an equidigital number, since it uses as much as digits as its factorization.

256641311 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 29.

The square root of 256641311 is about 16020.0284331833. The cubic root of 256641311 is about 635.4901962306.

Adding to 256641311 its reverse (113146652), we get a palindrome (369787963).

The spelling of 256641311 in words is "two hundred fifty-six million, six hundred forty-one thousand, three hundred eleven".