256288081 has 9 divisors (see below), whose sum is σ = 298261449. Its totient is φ = 219579444.

The previous prime is 256288079. The next prime is 256288091. The reversal of 256288081 is 180882652.

It is a happy number.

The square root of 256288081 is 16009.

It is a perfect power (a square), and thus also a powerful number.

256288081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 256288081 - 2¹ = 256288079 is a prime.

It is a super-2 number, since 2×256288081² = 131367160925325122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256288031) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 110920 + ... + 113206.

It is an arithmetic number, because the mean of its divisors is an integer number (33140161).

Almost surely, 2^256288081 is an apocalyptic number.

256288081 is the 16009-th square number.

256288081 is the 8005-th centered octagonal number.

It is an amenable number.

256288081 is a deficient number, since it is larger than the sum of its proper divisors (41973368).

256288081 is an frugal number, since it uses more digits than its factorization.

256288081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4588 (or 2294 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 40.

The cubic root of 256288081 is about 635.1985086278.

The spelling of 256288081 in words is "two hundred fifty-six million, two hundred eighty-eight thousand, eighty-one".