260640 has 72 divisors (see below), whose sum is σ = 894348. Its totient is φ = 69120.

The previous prime is 260629. The next prime is 260647. The reversal of 260640 is 46062.

260640 is a `hidden beast` number, since 26 + 0 + 640 = 666.

260640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 219024 + 41616 = 468^2 + 204^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (260647) by changing a digit.

260640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1350 + ... + 1530.

2²⁶⁰⁶⁴⁰ is an apocalyptic number.

260640 is a gapful number since it is divisible by the number (20) 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 260640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (447174).

260640 is an abundant number, since it is smaller than the sum of its proper divisors (633708).

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

260640 is a wasteful number, since it uses less digits than its factorization.

260640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202 (or 191 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 260640 is about 510.5291372684. The cubic root of 260640 is about 63.8773693437.

It can be divided in two parts, 260 and 640, that added together give a square (900 = 30²).

The spelling of 260640 in words is "two hundred sixty thousand, six hundred forty".