21211233 has 8 divisors (see below), whose sum is σ = 28327200. Its totient is φ = 14118048.

The previous prime is 21211217. The next prime is 21211237. The reversal of 21211233 is 33211212.

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

It is not a de Polignac number, because 21211233 - 2⁴ = 21211217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21211237) 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, 3388 + ... + 7341.

It is an arithmetic number, because the mean of its divisors is an integer number (3540900).

Almost surely, 2^21211233 is an apocalyptic number.

It is an amenable number.

21211233 is a deficient number, since it is larger than the sum of its proper divisors (7115967).

21211233 is a wasteful number, since it uses less digits than its factorization.

21211233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11391.

The product of its digits is 72, while the sum is 15.

The square root of 21211233 is about 4605.5654375983. The cubic root of 21211233 is about 276.8143742814.

Adding to 21211233 its reverse (33211212), we get a palindrome (54422445).

The spelling of 21211233 in words is "twenty-one million, two hundred eleven thousand, two hundred thirty-three".