21324337 has 4 divisors (see below), whose sum is σ = 21393216. Its totient is φ = 21255460.

The previous prime is 21324313. The next prime is 21324361. The reversal of 21324337 is 73342312.

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 an interprime number because it is at equal distance from previous prime (21324313) and next prime (21324361).

It is a cyclic number.

It is not a de Polignac number, because 21324337 - 2¹¹ = 21322289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21324937) 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, 33973 + ... + 34594.

It is an arithmetic number, because the mean of its divisors is an integer number (5348304).

Almost surely, 2^21324337 is an apocalyptic number.

It is an amenable number.

21324337 is a deficient number, since it is larger than the sum of its proper divisors (68879).

21324337 is an equidigital number, since it uses as much as digits as its factorization.

21324337 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68878.

The product of its digits is 3024, while the sum is 25.

The square root of 21324337 is about 4617.8281691722. The cubic root of 21324337 is about 277.3055185767.

Adding to 21324337 its reverse (73342312), we get a palindrome (94666649).

The spelling of 21324337 in words is "twenty-one million, three hundred twenty-four thousand, three hundred thirty-seven".