256887893 has 2 divisors, whose sum is σ = 256887894. Its totient is φ = 256887892.

The previous prime is 256887823. The next prime is 256887931. The reversal of 256887893 is 398788652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 200307409 + 56580484 = 14153^2 + 7522^2 .

It is a cyclic number.

It is not a de Polignac number, because 256887893 - 2¹⁰ = 256886869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256887823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128443946 + 128443947.

It is an arithmetic number, because the mean of its divisors is an integer number (128443947).

Almost surely, 2^256887893 is an apocalyptic number.

It is an amenable number.

256887893 is a deficient number, since it is larger than the sum of its proper divisors (1).

256887893 is an equidigital number, since it uses as much as digits as its factorization.

256887893 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5806080, while the sum is 56.

The square root of 256887893 is about 16027.7226392273. The cubic root of 256887893 is about 635.6936582578.

The spelling of 256887893 in words is "two hundred fifty-six million, eight hundred eighty-seven thousand, eight hundred ninety-three".