256740240771 has 24 divisors (see below), whose sum is σ = 423919458144. Its totient is φ = 146676067200.

The previous prime is 256740240767. The next prime is 256740240793. The reversal of 256740240771 is 177042047652.

256740240771 is a `hidden beast` number, since 2 + 567 + 40 + 2 + 40 + 7 + 7 + 1 = 666.

It is not a de Polignac number, because 256740240771 - 2² = 256740240767 is a prime.

It is not an unprimeable number, because it can be changed into a prime (256740240271) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 166530 + ... + 735671.

It is an arithmetic number, because the mean of its divisors is an integer number (17663310756).

Almost surely, 2^256740240771 is an apocalyptic number.

256740240771 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

256740240771 is a deficient number, since it is larger than the sum of its proper divisors (167179217373).

256740240771 is a wasteful number, since it uses less digits than its factorization.

256740240771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 906731 (or 906728 counting only the distinct ones).

The product of its (nonzero) digits is 658560, while the sum is 45.

The spelling of 256740240771 in words is "two hundred fifty-six billion, seven hundred forty million, two hundred forty thousand, seven hundred seventy-one".