24021 has 12 divisors (see below), whose sum is σ = 36972. Its totient is φ = 14976.

The previous prime is 24019. The next prime is 24023. The reversal of 24021 is 12042.

24021 is nontrivially palindromic in base 16.

It is an interprime number because it is at equal distance from previous prime (24019) and next prime (24023).

It can be written as a sum of positive squares in 2 ways, for example, as 12996 + 11025 = 114^2 + 105^2 .

It is not a de Polignac number, because 24021 - 2¹ = 24019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 23994 and 24012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (24023) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 75 + ... + 231.

It is an arithmetic number, because the mean of its divisors is an integer number (3081).

2²⁴⁰²¹ is an apocalyptic number.

It is an amenable number.

24021 is a deficient number, since it is larger than the sum of its proper divisors (12951).

24021 is a wasteful number, since it uses less digits than its factorization.

24021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 24021 is about 154.9870962371. The cubic root of 24021 is about 28.8534020760.

Adding to 24021 its reverse (12042), we get a palindrome (36063).

The spelling of 24021 in words is "twenty-four thousand, twenty-one", and thus it is an iban number.