256724939 has 4 divisors (see below), whose sum is σ = 271826424. Its totient is φ = 241623456.

The previous prime is 256724929. The next prime is 256724947. The reversal of 256724939 is 939427652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 256724939 - 2¹² = 256720843 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 256724893 and 256724902.

It is not an unprimeable number, because it can be changed into a prime (256724929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7550717 + ... + 7550750.

It is an arithmetic number, because the mean of its divisors is an integer number (67956606).

Almost surely, 2^256724939 is an apocalyptic number.

256724939 is a deficient number, since it is larger than the sum of its proper divisors (15101485).

256724939 is a wasteful number, since it uses less digits than its factorization.

256724939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15101484.

The product of its digits is 816480, while the sum is 47.

The square root of 256724939 is about 16022.6383283153. The cubic root of 256724939 is about 635.5592147406.

The spelling of 256724939 in words is "two hundred fifty-six million, seven hundred twenty-four thousand, nine hundred thirty-nine".