256512005 has 8 divisors (see below), whose sum is σ = 309853824. Its totient is φ = 203850000.

The previous prime is 256511987. The next prime is 256512007. The reversal of 256512005 is 500215652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-256512005 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256512007) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 169121 + ... + 170630.

It is an arithmetic number, because the mean of its divisors is an integer number (38731728).

Almost surely, 2^256512005 is an apocalyptic number.

It is an amenable number.

256512005 is a deficient number, since it is larger than the sum of its proper divisors (53341819).

256512005 is a wasteful number, since it uses less digits than its factorization.

256512005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339907.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 256512005 is about 16015.9921640840. The cubic root of 256512005 is about 635.3834499713.

Adding to 256512005 its reverse (500215652), we get a palindrome (756727657).

The spelling of 256512005 in words is "two hundred fifty-six million, five hundred twelve thousand, five".