256464415439 has 2 divisors, whose sum is σ = 256464415440. Its totient is φ = 256464415438.

The previous prime is 256464415421. The next prime is 256464415447. The reversal of 256464415439 is 934514464652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256464415439 - 2⁸ = 256464415183 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256464475439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128232207719 + 128232207720.

It is an arithmetic number, because the mean of its divisors is an integer number (128232207720).

Almost surely, 2^256464415439 is an apocalyptic number.

256464415439 is a deficient number, since it is larger than the sum of its proper divisors (1).

256464415439 is an equidigital number, since it uses as much as digits as its factorization.

256464415439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12441600, while the sum is 53.

The spelling of 256464415439 in words is "two hundred fifty-six billion, four hundred sixty-four million, four hundred fifteen thousand, four hundred thirty-nine".