21233212 has 48 divisors (see below), whose sum is σ = 49900032. Its totient is φ = 7634880.

The previous prime is 21233197. The next prime is 21233213.

21233212 = T₁₄₃ + T₁₄₄ + ... + T₅₀₆.

21233212 is nontrivially palindromic in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21233213) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1353 + ... + 6655.

It is an arithmetic number, because the mean of its divisors is an integer number (1039584).

Almost surely, 2^21233212 is an apocalyptic number.

21233212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21233212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24950016).

21233212 is an abundant number, since it is smaller than the sum of its proper divisors (28666820).

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

21233212 is a wasteful number, since it uses less digits than its factorization.

21233212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5338 (or 5336 counting only the distinct ones).

The product of its digits is 144, while the sum is 16.

The square root of 21233212 is about 4607.9509546001. The cubic root of 21233212 is about 276.9099526148.

It can be divided in two parts, 2123 and 3212, that added together give a palindrome (5335).

The spelling of 21233212 in words is "twenty-one million, two hundred thirty-three thousand, two hundred twelve".