261844 has 18 divisors (see below), whose sum is σ = 504602. Its totient is φ = 118800.

The previous prime is 261823. The next prime is 261847. The reversal of 261844 is 448162.

It can be written as a sum of positive squares in only one way, i.e., 213444 + 48400 = 462^2 + 220^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261847) 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 5 ways as a sum of consecutive naturals, for example, 214 + ... + 754.

2²⁶¹⁸⁴⁴ is an apocalyptic number.

It is an amenable number.

261844 is a deficient number, since it is larger than the sum of its proper divisors (242758).

261844 is a wasteful number, since it uses less digits than its factorization.

261844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 567 (or 554 counting only the distinct ones).

The product of its digits is 1536, while the sum is 25.

The square root of 261844 is about 511.7069473830. The cubic root of 261844 is about 63.9755766183.

It can be divided in two parts, 2618 and 44, that added together give a palindrome (2662).

The spelling of 261844 in words is "two hundred sixty-one thousand, eight hundred forty-four".