256915975 has 12 divisors (see below), whose sum is σ = 327187144. Its totient is φ = 199977120.

The previous prime is 256915969. The next prime is 256915991. The reversal of 256915975 is 579519652.

It is not a de Polignac number, because 256915975 - 2¹¹ = 256913927 is a prime.

It is a hoax number, since the sum of its digits (49) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 137949 + ... + 139798.

Almost surely, 2^256915975 is an apocalyptic number.

256915975 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

256915975 is a deficient number, since it is larger than the sum of its proper divisors (70271169).

256915975 is a wasteful number, since it uses less digits than its factorization.

256915975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277794 (or 277789 counting only the distinct ones).

The product of its digits is 850500, while the sum is 49.

The square root of 256915975 is about 16028.5986598954. The cubic root of 256915975 is about 635.7168212787.

The spelling of 256915975 in words is "two hundred fifty-six million, nine hundred fifteen thousand, nine hundred seventy-five".