21323533 has 8 divisors (see below), whose sum is σ = 26585280. Its totient is φ = 16615680.

The previous prime is 21323531. The next prime is 21323591. The reversal of 21323533 is 33532312.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21323533 - 2¹ = 21323531 is a prime.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21323531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 138388 + ... + 138541.

It is an arithmetic number, because the mean of its divisors is an integer number (3323160).

Almost surely, 2^21323533 is an apocalyptic number.

It is an amenable number.

21323533 is a deficient number, since it is larger than the sum of its proper divisors (5261747).

21323533 is a wasteful number, since it uses less digits than its factorization.

21323533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276947.

The product of its digits is 1620, while the sum is 22.

The square root of 21323533 is about 4617.7411144411. The cubic root of 21323533 is about 277.3020334126.

Adding to 21323533 its reverse (33532312), we get a palindrome (54855845).

It can be divided in two parts, 2132 and 3533, that added together give a palindrome (5665).

The spelling of 21323533 in words is "twenty-one million, three hundred twenty-three thousand, five hundred thirty-three".