256515105 has 64 divisors (see below), whose sum is σ = 538675200. Its totient is φ = 100984320.

The previous prime is 256515097. The next prime is 256515151. The reversal of 256515105 is 501515652.

It is not a de Polignac number, because 256515105 - 2³ = 256515097 is a prime.

It is a super-2 number, since 2×256515105² = 131599998186322050, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 16101 + ... + 27789.

It is an arithmetic number, because the mean of its divisors is an integer number (8416800).

Almost surely, 2^256515105 is an apocalyptic number.

It is an amenable number.

256515105 is an abundant number, since it is smaller than the sum of its proper divisors (282160095).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256515105 is a wasteful number, since it uses less digits than its factorization.

256515105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11734.

The product of its (nonzero) digits is 7500, while the sum is 30.

The square root of 256515105 is about 16016.0889420607. The cubic root of 256515105 is about 635.3860095406.

The spelling of 256515105 in words is "two hundred fifty-six million, five hundred fifteen thousand, one hundred five".