24040021 has 4 divisors (see below), whose sum is σ = 24079852. Its totient is φ = 24000192.

The previous prime is 24040013. The next prime is 24040031. The reversal of 24040021 is 12004042.

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 1134225 + 22905796 = 1065^2 + 4786^2 .

It is a cyclic number.

It is not a de Polignac number, because 24040021 - 2³ = 24040013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 24039983 and 24040010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (24040031) 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, 18996 + ... + 20221.

It is an arithmetic number, because the mean of its divisors is an integer number (6019963).

Almost surely, 2^24040021 is an apocalyptic number.

It is an amenable number.

24040021 is a deficient number, since it is larger than the sum of its proper divisors (39831).

24040021 is an equidigital number, since it uses as much as digits as its factorization.

24040021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39830.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 24040021 is about 4903.0624103717. The cubic root of 24040021 is about 288.6101591062.

Adding to 24040021 its reverse (12004042), we get a palindrome (36044063).

The spelling of 24040021 in words is "twenty-four million, forty thousand, twenty-one".