256061505 has 64 divisors (see below), whose sum is σ = 482342400. Its totient is φ = 115944192.

The previous prime is 256061501. The next prime is 256061527. The reversal of 256061505 is 505160652.

It is not a de Polignac number, because 256061505 - 2² = 256061501 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256061501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 807607 + ... + 807923.

It is an arithmetic number, because the mean of its divisors is an integer number (7536600).

Almost surely, 2^256061505 is an apocalyptic number.

It is an amenable number.

256061505 is a deficient number, since it is larger than the sum of its proper divisors (226280895).

256061505 is a wasteful number, since it uses less digits than its factorization.

256061505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503 (or 489 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 30.

The square root of 256061505 is about 16001.9219158200. The cubic root of 256061505 is about 635.0112672893.

The spelling of 256061505 in words is "two hundred fifty-six million, sixty-one thousand, five hundred five".