256581363 has 4 divisors (see below), whose sum is σ = 342108488. Its totient is φ = 171054240.

The previous prime is 256581361. The next prime is 256581371. The reversal of 256581363 is 363185652.

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

It is not a de Polignac number, because 256581363 - 2¹ = 256581361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256581361) 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, 42763558 + ... + 42763563.

It is an arithmetic number, because the mean of its divisors is an integer number (85527122).

Almost surely, 2^256581363 is an apocalyptic number.

256581363 is a deficient number, since it is larger than the sum of its proper divisors (85527125).

256581363 is an equidigital number, since it uses as much as digits as its factorization.

256581363 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85527124.

The product of its digits is 129600, while the sum is 39.

The square root of 256581363 is about 16018.1572910245. The cubic root of 256581363 is about 635.4407116890.

The spelling of 256581363 in words is "two hundred fifty-six million, five hundred eighty-one thousand, three hundred sixty-three".