256291739 has 12 divisors (see below), whose sum is σ = 286267032. Its totient is φ = 227556000.

The previous prime is 256291709. The next prime is 256291759. The reversal of 256291739 is 937192652.

It is a de Polignac number, because none of the positive numbers 2^k-256291739 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256291739.

It is not an unprimeable number, because it can be changed into a prime (256291709) 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 11 ways as a sum of consecutive naturals, for example, 14039 + ... + 26639.

It is an arithmetic number, because the mean of its divisors is an integer number (23855586).

Almost surely, 2^256291739 is an apocalyptic number.

256291739 is a deficient number, since it is larger than the sum of its proper divisors (29975293).

256291739 is a wasteful number, since it uses less digits than its factorization.

256291739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12698 (or 12655 counting only the distinct ones).

The product of its digits is 204120, while the sum is 44.

The square root of 256291739 is about 16009.1142478277. The cubic root of 256291739 is about 635.2015306764.

The spelling of 256291739 in words is "two hundred fifty-six million, two hundred ninety-one thousand, seven hundred thirty-nine".