21222220100121 has 12 divisors (see below), whose sum is σ = 30654718756272. Its totient is φ = 14147961733176.

The previous prime is 21222220100119. The next prime is 21222220100129. The reversal of 21222220100121 is 12100102222212.

It is a happy number.

21222220100121 is a `hidden beast` number, since 2 + 1 + 222 + 220 + 100 + 121 = 666.

It is not a de Polignac number, because 21222220100121 - 2¹ = 21222220100119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21222220100094 and 21222220100103.

It is not an unprimeable number, because it can be changed into a prime (21222220100129) 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, 14688351 + ... + 16068356.

It is an arithmetic number, because the mean of its divisors is an integer number (2554559896356).

Almost surely, 2^{21222220100121} is an apocalyptic number.

It is an amenable number.

21222220100121 is a deficient number, since it is larger than the sum of its proper divisors (9432498656151).

21222220100121 is a wasteful number, since it uses less digits than its factorization.

21222220100121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30833380 (or 30833377 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21222220100121 its reverse (12100102222212), we get a palindrome (33322322322333).

The spelling of 21222220100121 in words is "twenty-one trillion, two hundred twenty-two billion, two hundred twenty million, one hundred thousand, one hundred twenty-one".