21222212 has 12 divisors (see below), whose sum is σ = 40515216. Its totient is φ = 9646440.

The previous prime is 21222211. The next prime is 21222251.

21222212 is nontrivially palindromic in base 10.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21222211) 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, 241118 + ... + 241205.

It is an arithmetic number, because the mean of its divisors is an integer number (3376268).

Almost surely, 2^21222212 is an apocalyptic number.

21222212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21222212 is a deficient number, since it is larger than the sum of its proper divisors (19293004).

21222212 is a wasteful number, since it uses less digits than its factorization.

21222212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 482338 (or 482336 counting only the distinct ones).

The product of its digits is 64, while the sum is 14.

The square root of 21222212 is about 4606.7572108806. The cubic root of 21222212 is about 276.8621260364.

It can be divided in two parts, 2122 and 2212, that added together give a palindrome (4334).

The spelling of 21222212 in words is "twenty-one million, two hundred twenty-two thousand, two hundred twelve".