256433247 has 24 divisors (see below), whose sum is σ = 423989280. Its totient is φ = 146301120.

The previous prime is 256433237. The next prime is 256433249. The reversal of 256433247 is 742334652.

256433247 is a `hidden beast` number, since 2 + 5 + 643 + 3 + 2 + 4 + 7 = 666.

It is not a de Polignac number, because 256433247 - 2⁸ = 256432991 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256433249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 41797 + ... + 47537.

It is an arithmetic number, because the mean of its divisors is an integer number (17666220).

Almost surely, 2^256433247 is an apocalyptic number.

256433247 is a deficient number, since it is larger than the sum of its proper divisors (167556033).

256433247 is a wasteful number, since it uses less digits than its factorization.

256433247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6463 (or 6460 counting only the distinct ones).

The product of its digits is 120960, while the sum is 36.

The square root of 256433247 is about 16013.5332453522. The cubic root of 256433247 is about 635.3184151307.

Adding to 256433247 its reverse (742334652), we get a palindrome (998767899).

The spelling of 256433247 in words is "two hundred fifty-six million, four hundred thirty-three thousand, two hundred forty-seven".