21242233 has 8 divisors (see below), whose sum is σ = 21490560. Its totient is φ = 20995680.

The previous prime is 21242203. The next prime is 21242237. The reversal of 21242233 is 33224212.

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 21242233 - 2⁵ = 21242201 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21242233.

It is not an unprimeable number, because it can be changed into a prime (21242237) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51733 + ... + 52141.

It is an arithmetic number, because the mean of its divisors is an integer number (2686320).

Almost surely, 2^21242233 is an apocalyptic number.

It is an amenable number.

21242233 is a deficient number, since it is larger than the sum of its proper divisors (248327).

21242233 is a wasteful number, since it uses less digits than its factorization.

21242233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 887.

The product of its digits is 576, while the sum is 19.

The square root of 21242233 is about 4608.9297022194. The cubic root of 21242233 is about 276.9491624307.

Adding to 21242233 its reverse (33224212), we get a palindrome (54466445).

The spelling of 21242233 in words is "twenty-one million, two hundred forty-two thousand, two hundred thirty-three".