261088256 has 88 divisors (see below), whose sum is σ = 613510464. Its totient is φ = 109486080.

The previous prime is 261088187. The next prime is 261088259. The reversal of 261088256 is 652880162.

It is a tau number, because it is divible by the number of its divisors (88).

It is a super-2 number, since 2×261088256² = 136334154842243072, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (261088259) 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 7 ways as a sum of consecutive naturals, for example, 145541 + ... + 147323.

Almost surely, 2^261088256 is an apocalyptic number.

261088256 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261088256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (306755232).

261088256 is an abundant number, since it is smaller than the sum of its proper divisors (352422208).

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

261088256 is a wasteful number, since it uses less digits than its factorization.

261088256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1827 (or 1809 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 38.

The square root of 261088256 is about 16158.2256451629. The cubic root of 261088256 is about 639.1396773593.

The spelling of 261088256 in words is "two hundred sixty-one million, eighty-eight thousand, two hundred fifty-six".