256585712077 has 4 divisors (see below), whose sum is σ = 271678989276. Its totient is φ = 241492434880.

The previous prime is 256585712057. The next prime is 256585712093. The reversal of 256585712077 is 770217585652.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 191869404841 + 64716307236 = 438029^2 + 254394^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256585712077 is a prime.

It is a super-2 number, since 2×256585712077² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256585712027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7546638574 + ... + 7546638607.

It is an arithmetic number, because the mean of its divisors is an integer number (67919747319).

Almost surely, 2^256585712077 is an apocalyptic number.

It is an amenable number.

256585712077 is a deficient number, since it is larger than the sum of its proper divisors (15093277199).

256585712077 is a wasteful number, since it uses less digits than its factorization.

256585712077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15093277198.

The product of its (nonzero) digits is 8232000, while the sum is 55.

The spelling of 256585712077 in words is "two hundred fifty-six billion, five hundred eighty-five million, seven hundred twelve thousand, seventy-seven".