21211021111222 has 4 divisors (see below), whose sum is σ = 31816531666836. Its totient is φ = 10605510555610.

The previous prime is 21211021111183. The next prime is 21211021111223. The reversal of 21211021111222 is 22211112011212.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21211021111222.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211021111223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5302755277804 + ... + 5302755277807.

It is an arithmetic number, because the mean of its divisors is an integer number (7954132916709).

Almost surely, 2^{21211021111222} is an apocalyptic number.

21211021111222 is a deficient number, since it is larger than the sum of its proper divisors (10605510555614).

21211021111222 is a wasteful number, since it uses less digits than its factorization.

21211021111222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10605510555613.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21211021111222 its reverse (22211112011212), we get a palindrome (43422133122434).

The spelling of 21211021111222 in words is "twenty-one trillion, two hundred eleven billion, twenty-one million, one hundred eleven thousand, two hundred twenty-two".