256864133 has 2 divisors, whose sum is σ = 256864134. Its totient is φ = 256864132.

The previous prime is 256864121. The next prime is 256864199. The reversal of 256864133 is 331468652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 169572484 + 87291649 = 13022^2 + 9343^2 .

It is a cyclic number.

It is not a de Polignac number, because 256864133 - 2¹⁴ = 256847749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256863133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128432066 + 128432067.

It is an arithmetic number, because the mean of its divisors is an integer number (128432067).

Almost surely, 2^256864133 is an apocalyptic number.

It is an amenable number.

256864133 is a deficient number, since it is larger than the sum of its proper divisors (1).

256864133 is an equidigital number, since it uses as much as digits as its factorization.

256864133 is an evil number, because the sum of its binary digits is even.

The product of its digits is 103680, while the sum is 38.

The square root of 256864133 is about 16026.9814063660. The cubic root of 256864133 is about 635.6740588561.

The spelling of 256864133 in words is "two hundred fifty-six million, eight hundred sixty-four thousand, one hundred thirty-three".