256813363 has 2 divisors, whose sum is σ = 256813364. Its totient is φ = 256813362.

The previous prime is 256813351. The next prime is 256813369. The reversal of 256813363 is 363318652.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256813363 - 2¹⁷ = 256682291 is a prime.

It is not a weakly prime, because it can be changed into another prime (256813369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128406681 + 128406682.

It is an arithmetic number, because the mean of its divisors is an integer number (128406682).

Almost surely, 2^256813363 is an apocalyptic number.

256813363 is a deficient number, since it is larger than the sum of its proper divisors (1).

256813363 is an equidigital number, since it uses as much as digits as its factorization.

256813363 is an evil number, because the sum of its binary digits is even.

The product of its digits is 77760, while the sum is 37.

The square root of 256813363 is about 16025.3974365692. The cubic root of 256813363 is about 635.6321751073.

It can be divided in two parts, 2568 and 13363, that added together give a triangular number (15931 = T₁₇₈).

The spelling of 256813363 in words is "two hundred fifty-six million, eight hundred thirteen thousand, three hundred sixty-three".