21211222222 has 4 divisors (see below), whose sum is σ = 31816833336. Its totient is φ = 10605611110.

The previous prime is 21211222217. The next prime is 21211222231. The reversal of 21211222222 is 22222211212.

It is a semiprime because it is the product of two primes.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21211222222.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5302805554 + ... + 5302805557.

It is an arithmetic number, because the mean of its divisors is an integer number (7954208334).

Almost surely, 2^21211222222 is an apocalyptic number.

21211222222 is a deficient number, since it is larger than the sum of its proper divisors (10605611114).

21211222222 is a wasteful number, since it uses less digits than its factorization.

21211222222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10605611113.

The product of its digits is 256, while the sum is 19.

Adding to 21211222222 its reverse (22222211212), we get a palindrome (43433433434).

The spelling of 21211222222 in words is "twenty-one billion, two hundred eleven million, two hundred twenty-two thousand, two hundred twenty-two".