256187456 has 28 divisors (see below), whose sum is σ = 580997568. Its totient is φ = 109794432.

The previous prime is 256187447. The next prime is 256187473. The reversal of 256187456 is 654781652.

It is a tau number, because it is divible by the number of its divisors (28).

It is a super-2 number, since 2×256187456² = 131264025223503872, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 285476 + ... + 286371.

Almost surely, 2^256187456 is an apocalyptic number.

It is an amenable number.

256187456 is an abundant number, since it is smaller than the sum of its proper divisors (324810112).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256187456 is an equidigital number, since it uses as much as digits as its factorization.

256187456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 571866 (or 571856 counting only the distinct ones).

The product of its digits is 403200, while the sum is 44.

The square root of 256187456 is about 16005.8569280123. The cubic root of 256187456 is about 635.1153662299.

The spelling of 256187456 in words is "two hundred fifty-six million, one hundred eighty-seven thousand, four hundred fifty-six".