2561256 has 24 divisors (see below), whose sum is σ = 6936930. Its totient is φ = 853728.

The previous prime is 2561239. The next prime is 2561261. The reversal of 2561256 is 6521652.

It can be written as a sum of positive squares in only one way, i.e., 2452356 + 108900 = 1566^2 + 330^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17715 + ... + 17858.

2^2561256 is an apocalyptic number.

It is an amenable number.

2561256 is an abundant number, since it is smaller than the sum of its proper divisors (4375674).

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

2561256 is a wasteful number, since it uses less digits than its factorization.

2561256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35585 (or 35578 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 2561256 is about 1600.3924518692. The cubic root of 2561256 is about 136.8204442617.

The spelling of 2561256 in words is "two million, five hundred sixty-one thousand, two hundred fifty-six".