243641 has 4 divisors (see below), whose sum is σ = 248292. Its totient is φ = 238992.

The previous prime is 243631. The next prime is 243643. The reversal of 243641 is 146342.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 87616 + 156025 = 296^2 + 395^2 .

It is a cyclic number.

It is not a de Polignac number, because 243641 - 2⁶ = 243577 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (243643) 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 3 ways as a sum of consecutive naturals, for example, 2246 + ... + 2351.

It is an arithmetic number, because the mean of its divisors is an integer number (62073).

2²⁴³⁶⁴¹ is an apocalyptic number.

It is an amenable number.

243641 is a deficient number, since it is larger than the sum of its proper divisors (4651).

243641 is an equidigital number, since it uses as much as digits as its factorization.

243641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4650.

The product of its digits is 576, while the sum is 20.

The square root of 243641 is about 493.6000405186. The cubic root of 243641 is about 62.4573362168.

Adding to 243641 its reverse (146342), we get a palindrome (389983).

The spelling of 243641 in words is "two hundred forty-three thousand, six hundred forty-one".