261441 has 16 divisors (see below), whose sum is σ = 405120. Its totient is φ = 166320.

The previous prime is 261439. The next prime is 261451. The reversal of 261441 is 144162.

It is not a de Polignac number, because 261441 - 2¹ = 261439 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (261431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 411 + ... + 831.

It is an arithmetic number, because the mean of its divisors is an integer number (25320).

2²⁶¹⁴⁴¹ is an apocalyptic number.

It is an amenable number.

261441 is a deficient number, since it is larger than the sum of its proper divisors (143679).

261441 is a wasteful number, since it uses less digits than its factorization.

261441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 453 (or 447 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 261441 is about 511.3130156763. The cubic root of 261441 is about 63.9427384963.

The spelling of 261441 in words is "two hundred sixty-one thousand, four hundred forty-one".