243221 has 4 divisors (see below), whose sum is σ = 265344. Its totient is φ = 221100.

The previous prime is 243209. The next prime is 243227. The reversal of 243221 is 122342.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 243221 - 2⁶ = 243157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 243196 and 243205.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 243221.

It is not an unprimeable number, because it can be changed into a prime (243227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11045 + ... + 11066.

It is an arithmetic number, because the mean of its divisors is an integer number (66336).

2²⁴³²²¹ is an apocalyptic number.

It is an amenable number.

243221 is a deficient number, since it is larger than the sum of its proper divisors (22123).

243221 is a wasteful number, since it uses less digits than its factorization.

243221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22122.

The product of its digits is 96, while the sum is 14.

The square root of 243221 is about 493.1744113394. The cubic root of 243221 is about 62.4214265942.

Adding to 243221 its reverse (122342), we get a palindrome (365563).

It can be divided in two parts, 243 and 221, that added together give a palindrome (464).

The spelling of 243221 in words is "two hundred forty-three thousand, two hundred twenty-one", and thus it is an iban number.