21222122220121 has 12 divisors (see below), whose sum is σ = 22399415500800. Its totient is φ = 20103774893208.

The previous prime is 21222122220119. The next prime is 21222122220161. The reversal of 21222122220121 is 12102222122212.

It is not a de Polignac number, because 21222122220121 - 2¹ = 21222122220119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21222122220092 and 21222122220101.

It is not an unprimeable number, because it can be changed into a prime (21222122220161) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3196840 + ... + 7256998.

It is an arithmetic number, because the mean of its divisors is an integer number (1866617958400).

Almost surely, 2^{21222122220121} is an apocalyptic number.

It is an amenable number.

21222122220121 is a deficient number, since it is larger than the sum of its proper divisors (1177293280679).

21222122220121 is a wasteful number, since it uses less digits than its factorization.

21222122220121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4074676 (or 4074657 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 21222122220121 its reverse (12102222122212), we get a palindrome (33324344342333).

The spelling of 21222122220121 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred twenty-two million, two hundred twenty thousand, one hundred twenty-one".