256647525 has 24 divisors (see below), whose sum is σ = 428302944. Its totient is φ = 135595200.

The previous prime is 256647509. The next prime is 256647527. The reversal of 256647525 is 525746652.

It is not a de Polignac number, because 256647525 - 2⁴ = 256647509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256647527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7966 + ... + 24015.

It is an arithmetic number, because the mean of its divisors is an integer number (17845956).

Almost surely, 2^256647525 is an apocalyptic number.

256647525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

256647525 is a deficient number, since it is larger than the sum of its proper divisors (171655419).

256647525 is a wasteful number, since it uses less digits than its factorization.

256647525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32101 (or 32096 counting only the distinct ones).

The product of its digits is 504000, while the sum is 42.

The square root of 256647525 is about 16020.2223767337. Note that the first 3 decimals coincide. The cubic root of 256647525 is about 635.4953251843.

The spelling of 256647525 in words is "two hundred fifty-six million, six hundred forty-seven thousand, five hundred twenty-five".