21233766 has 16 divisors (see below), whose sum is σ = 42541488. Its totient is φ = 7065600.

The previous prime is 21233753. The next prime is 21233813. The reversal of 21233766 is 66733212.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1086 + ... + 6606.

It is an arithmetic number, because the mean of its divisors is an integer number (2658843).

Almost surely, 2^21233766 is an apocalyptic number.

21233766 is an abundant number, since it is smaller than the sum of its proper divisors (21307722).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21233766 is a wasteful number, since it uses less digits than its factorization.

21233766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6167.

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

The square root of 21233766 is about 4608.0110676950. The cubic root of 21233766 is about 276.9123608982.

Adding to 21233766 its reverse (66733212), we get a palindrome (87966978).

The spelling of 21233766 in words is "twenty-one million, two hundred thirty-three thousand, seven hundred sixty-six".