21222221212222 has 4 divisors (see below), whose sum is σ = 31833331818336. Its totient is φ = 10611110606110.

The previous prime is 21222221212217. The next prime is 21222221212243. The reversal of 21222221212222 is 22221212222212.

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 congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5305555303054 + ... + 5305555303057.

It is an arithmetic number, because the mean of its divisors is an integer number (7958332954584).

Almost surely, 2^{21222221212222} is an apocalyptic number.

21222221212222 is a deficient number, since it is larger than the sum of its proper divisors (10611110606114).

21222221212222 is a wasteful number, since it uses less digits than its factorization.

21222221212222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10611110606113.

The product of its digits is 2048, while the sum is 25.

Adding to 21222221212222 its reverse (22221212222212), we get a palindrome (43443433434434).

The spelling of 21222221212222 in words is "twenty-one trillion, two hundred twenty-two billion, two hundred twenty-one million, two hundred twelve thousand, two hundred twenty-two".