21766233 has 8 divisors (see below), whose sum is σ = 29063296. Its totient is φ = 14490000.

The previous prime is 21766231. The next prime is 21766237. The reversal of 21766233 is 33266712.

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

It is not a de Polignac number, because 21766233 - 2¹ = 21766231 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 21766233.

It is not an unprimeable number, because it can be changed into a prime (21766231) 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, 2578 + ... + 7083.

It is an arithmetic number, because the mean of its divisors is an integer number (3632912).

Almost surely, 2^21766233 is an apocalyptic number.

It is an amenable number.

21766233 is a deficient number, since it is larger than the sum of its proper divisors (7297063).

21766233 is an equidigital number, since it uses as much as digits as its factorization.

21766233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10415.

The product of its digits is 9072, while the sum is 30.

The square root of 21766233 is about 4665.4295622161. The cubic root of 21766233 is about 279.2079358409.

The spelling of 21766233 in words is "twenty-one million, seven hundred sixty-six thousand, two hundred thirty-three".