21333433 has 4 divisors (see below), whose sum is σ = 23272848. Its totient is φ = 19394020.

The previous prime is 21333413. The next prime is 21333437. The reversal of 21333433 is 33433312.

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 21333433 - 2⁹ = 21332921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21333437) 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, 969691 + ... + 969712.

It is an arithmetic number, because the mean of its divisors is an integer number (5818212).

Almost surely, 2^21333433 is an apocalyptic number.

It is an amenable number.

21333433 is a deficient number, since it is larger than the sum of its proper divisors (1939415).

21333433 is a wasteful number, since it uses less digits than its factorization.

21333433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1939414.

The product of its digits is 1944, while the sum is 22.

The square root of 21333433 is about 4618.8129427376. The cubic root of 21333433 is about 277.3449416459.

Adding to 21333433 its reverse (33433312), we get a palindrome (54766745).

The spelling of 21333433 in words is "twenty-one million, three hundred thirty-three thousand, four hundred thirty-three".