21221112212122 has 4 divisors (see below), whose sum is σ = 31831668318186. Its totient is φ = 10610556106060.

The previous prime is 21221112212119. The next prime is 21221112212159. The reversal of 21221112212122 is 22121221112212.

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

It can be written as a sum of positive squares in only one way, i.e., 20521180860961 + 699931351161 = 4530031^2 + 836619^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 21221112212093 and 21221112212102.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5305278053029 + ... + 5305278053032.

Almost surely, 2^{21221112212122} is an apocalyptic number.

21221112212122 is a deficient number, since it is larger than the sum of its proper divisors (10610556106064).

21221112212122 is a wasteful number, since it uses less digits than its factorization.

21221112212122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10610556106063.

The product of its digits is 256, while the sum is 22.

Adding to 21221112212122 its reverse (22121221112212), we get a palindrome (43342333324334).

The spelling of 21221112212122 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twelve million, two hundred twelve thousand, one hundred twenty-two".