256445511 has 16 divisors (see below), whose sum is σ = 391404288. Its totient is φ = 146304000.

The previous prime is 256445491. The next prime is 256445513. The reversal of 256445511 is 115544652.

It is not a de Polignac number, because 256445511 - 2⁵ = 256445479 is a prime.

It is a super-2 number, since 2×256445511² = 131528600224102242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256445513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3936 + ... + 22986.

It is an arithmetic number, because the mean of its divisors is an integer number (24462768).

Almost surely, 2^256445511 is an apocalyptic number.

256445511 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

256445511 is a deficient number, since it is larger than the sum of its proper divisors (134958777).

256445511 is a wasteful number, since it uses less digits than its factorization.

256445511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19702.

The product of its digits is 24000, while the sum is 33.

The square root of 256445511 is about 16013.9161668844. The cubic root of 256445511 is about 635.3285430697.

The spelling of 256445511 in words is "two hundred fifty-six million, four hundred forty-five thousand, five hundred eleven".