261261256 has 32 divisors (see below), whose sum is σ = 498674880. Its totient is φ = 128296000.

The previous prime is 261261223. The next prime is 261261271. The reversal of 261261256 is 652162162.

261261256 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 179331 + ... + 180781.

It is an arithmetic number, because the mean of its divisors is an integer number (15583590).

Almost surely, 2^261261256 is an apocalyptic number.

It is an amenable number.

261261256 is a deficient number, since it is larger than the sum of its proper divisors (237413624).

261261256 is a wasteful number, since it uses less digits than its factorization.

261261256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1845 (or 1841 counting only the distinct ones).

The product of its digits is 8640, while the sum is 31.

The square root of 261261256 is about 16163.5780692271. The cubic root of 261261256 is about 639.2808132252.

The spelling of 261261256 in words is "two hundred sixty-one million, two hundred sixty-one thousand, two hundred fifty-six".