21433343 has 4 divisors (see below), whose sum is σ = 21796680. Its totient is φ = 21070008.

The previous prime is 21433319. The next prime is 21433351. The reversal of 21433343 is 34333412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21433343 - 2¹⁶ = 21367807 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21436343) 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, 181580 + ... + 181697.

It is an arithmetic number, because the mean of its divisors is an integer number (5449170).

Almost surely, 2^21433343 is an apocalyptic number.

21433343 is a deficient number, since it is larger than the sum of its proper divisors (363337).

21433343 is an equidigital number, since it uses as much as digits as its factorization.

21433343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363336.

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

The square root of 21433343 is about 4629.6158587943. The cubic root of 21433343 is about 277.7772269441. Note that the first 3 decimals are identical.

Adding to 21433343 its reverse (34333412), we get a palindrome (55766755).

The spelling of 21433343 in words is "twenty-one million, four hundred thirty-three thousand, three hundred forty-three".