256244813 has 4 divisors (see below), whose sum is σ = 279539808. Its totient is φ = 232949820.

The previous prime is 256244801. The next prime is 256244831. The reversal of 256244813 is 318442652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 256244813 - 2⁴ = 256244797 is a prime.

It is a super-2 number, since 2×256244813² = 131322808378809938, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256244843) 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 in 3 ways as a sum of consecutive naturals, for example, 11647481 + ... + 11647502.

It is an arithmetic number, because the mean of its divisors is an integer number (69884952).

Almost surely, 2^256244813 is an apocalyptic number.

It is an amenable number.

256244813 is a deficient number, since it is larger than the sum of its proper divisors (23294995).

256244813 is a wasteful number, since it uses less digits than its factorization.

256244813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23294994.

The product of its digits is 46080, while the sum is 35.

The square root of 256244813 is about 16007.6485781017. The cubic root of 256244813 is about 635.1627606839.

The spelling of 256244813 in words is "two hundred fifty-six million, two hundred forty-four thousand, eight hundred thirteen".