21320324033 has 4 divisors (see below), whose sum is σ = 21329986560. Its totient is φ = 21310661508.

The previous prime is 21320323993. The next prime is 21320324089. The reversal of 21320324033 is 33042302312.

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 a cyclic number.

It is not a de Polignac number, because 21320324033 - 2¹⁰ = 21320323009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21320314033) 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, 4827953 + ... + 4832366.

It is an arithmetic number, because the mean of its divisors is an integer number (5332496640).

Almost surely, 2^21320324033 is an apocalyptic number.

It is an amenable number.

21320324033 is a deficient number, since it is larger than the sum of its proper divisors (9662527).

21320324033 is an equidigital number, since it uses as much as digits as its factorization.

21320324033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9662526.

The product of its (nonzero) digits is 2592, while the sum is 23.

Adding to 21320324033 its reverse (33042302312), we get a palindrome (54362626345).

The spelling of 21320324033 in words is "twenty-one billion, three hundred twenty million, three hundred twenty-four thousand, thirty-three".