256433257589 has 2 divisors, whose sum is σ = 256433257590. Its totient is φ = 256433257588.

The previous prime is 256433257583. The next prime is 256433257601. The reversal of 256433257589 is 985752334652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 256329564100 + 103693489 = 506290^2 + 10183^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256433257589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256433257583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128216628794 + 128216628795.

It is an arithmetic number, because the mean of its divisors is an integer number (128216628795).

Almost surely, 2^256433257589 is an apocalyptic number.

It is an amenable number.

256433257589 is a deficient number, since it is larger than the sum of its proper divisors (1).

256433257589 is an equidigital number, since it uses as much as digits as its factorization.

256433257589 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432000, while the sum is 59.

The spelling of 256433257589 in words is "two hundred fifty-six billion, four hundred thirty-three million, two hundred fifty-seven thousand, five hundred eighty-nine".