256506400515433 has 2 divisors, whose sum is σ = 256506400515434. Its totient is φ = 256506400515432.

The previous prime is 256506400515377. The next prime is 256506400515451. The reversal of 256506400515433 is 334515004605652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 253648688027904 + 2857712487529 = 15926352^2 + 1690477^2 .

It is a cyclic number.

It is not a de Polignac number, because 256506400515433 - 2¹⁷ = 256506400384361 is a prime.

It is not a weakly prime, because it can be changed into another prime (256506400525433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128253200257716 + 128253200257717.

It is an arithmetic number, because the mean of its divisors is an integer number (128253200257717).

Almost surely, 2^{256506400515433} is an apocalyptic number.

It is an amenable number.

256506400515433 is a deficient number, since it is larger than the sum of its proper divisors (1).

256506400515433 is an equidigital number, since it uses as much as digits as its factorization.

256506400515433 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480000, while the sum is 49.

The spelling of 256506400515433 in words is "two hundred fifty-six trillion, five hundred six billion, four hundred million, five hundred fifteen thousand, four hundred thirty-three".