21121222 has 32 divisors (see below), whose sum is σ = 34836480. Its totient is φ = 9572640.

The previous prime is 21121211. The next prime is 21121223. The reversal of 21121222 is 22212112.

It is a happy number.

It is a super-2 number, since 2×21121222² = 892212037546568, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121223) 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, 94603 + ... + 94825.

It is an arithmetic number, because the mean of its divisors is an integer number (1088640).

Almost surely, 2^21121222 is an apocalyptic number.

21121222 is a deficient number, since it is larger than the sum of its proper divisors (13715258).

21121222 is a wasteful number, since it uses less digits than its factorization.

21121222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 348.

The product of its digits is 32, while the sum is 13.

The square root of 21121222 is about 4595.7830671171. The cubic root of 21121222 is about 276.4222602448.

Adding to 21121222 its reverse (22212112), we get a palindrome (43333334).

The spelling of 21121222 in words is "twenty-one million, one hundred twenty-one thousand, two hundred twenty-two".