21335212 has 12 divisors (see below), whose sum is σ = 37894360. Its totient is φ = 10508256.

The previous prime is 21335207. The next prime is 21335219. The reversal of 21335212 is 21253312.

It is a self number, because there is not a number n which added to its sum of digits gives 21335212.

It is not an unprimeable number, because it can be changed into a prime (21335219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39537 + ... + 40072.

Almost surely, 2^21335212 is an apocalyptic number.

It is an amenable number.

21335212 is a deficient number, since it is larger than the sum of its proper divisors (16559148).

21335212 is a wasteful number, since it uses less digits than its factorization.

21335212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79680 (or 79678 counting only the distinct ones).

The product of its digits is 360, while the sum is 19.

The square root of 21335212 is about 4619.0055206722. The cubic root of 21335212 is about 277.3526507182.

Adding to 21335212 its reverse (21253312), we get a palindrome (42588524).

The spelling of 21335212 in words is "twenty-one million, three hundred thirty-five thousand, two hundred twelve".