256886249 has 4 divisors (see below), whose sum is σ = 257022864. Its totient is φ = 256749636.

The previous prime is 256886239. The next prime is 256886261. The reversal of 256886249 is 942688652.

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 256886249 - 2⁴ = 256886233 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 256886197 and 256886206.

It is not an unprimeable number, because it can be changed into a prime (256886209) 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, 65447 + ... + 69260.

It is an arithmetic number, because the mean of its divisors is an integer number (64255716).

Almost surely, 2^256886249 is an apocalyptic number.

It is an amenable number.

256886249 is a deficient number, since it is larger than the sum of its proper divisors (136615).

256886249 is a wasteful number, since it uses less digits than its factorization.

256886249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136614.

The product of its digits is 1658880, while the sum is 50.

The square root of 256886249 is about 16027.6713530070. The cubic root of 256886249 is about 635.6923021765.

The spelling of 256886249 in words is "two hundred fifty-six million, eight hundred eighty-six thousand, two hundred forty-nine".