24221 has 4 divisors (see below), whose sum is σ = 24732. Its totient is φ = 23712.

The previous prime is 24203. The next prime is 24223. The reversal of 24221 is 12242.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12242 = 2 ⋅6121.

It can be written as a sum of positive squares in 2 ways, for example, as 19321 + 4900 = 139^2 + 70^2 .

It is a cyclic number.

It is not a de Polignac number, because 24221 - 2¹⁰ = 23197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (24223) 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, 176 + ... + 281.

It is an arithmetic number, because the mean of its divisors is an integer number (6183).

2²⁴²²¹ is an apocalyptic number.

It is an amenable number.

24221 is a deficient number, since it is larger than the sum of its proper divisors (511).

24221 is an equidigital number, since it uses as much as digits as its factorization.

24221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510.

The product of its digits is 32, while the sum is 11.

The square root of 24221 is about 155.6309737809. The cubic root of 24221 is about 28.9332591238.

Adding to 24221 its reverse (12242), we get a palindrome (36463).

The spelling of 24221 in words is "twenty-four thousand, two hundred twenty-one", and thus it is an iban number.