261569256 has 32 divisors (see below), whose sum is σ = 704225760. Its totient is φ = 80482752.

The previous prime is 261569251. The next prime is 261569263. The reversal of 261569256 is 652965162.

It is not an unprimeable number, because it can be changed into a prime (261569251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 418870 + ... + 419493.

It is an arithmetic number, because the mean of its divisors is an integer number (22007055).

Almost surely, 2^261569256 is an apocalyptic number.

261569256 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

261569256 is an abundant number, since it is smaller than the sum of its proper divisors (442656504).

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

261569256 is a wasteful number, since it uses less digits than its factorization.

261569256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 838385 (or 838381 counting only the distinct ones).

The product of its digits is 194400, while the sum is 42.

The square root of 261569256 is about 16173.1028562858. The cubic root of 261569256 is about 639.5319298913.

The spelling of 261569256 in words is "two hundred sixty-one million, five hundred sixty-nine thousand, two hundred fifty-six".