121212222202221 has 4 divisors (see below), whose sum is σ = 161616296269632. Its totient is φ = 80808148134812.

The previous prime is 121212222202187. The next prime is 121212222202259. The reversal of 121212222202221 is 122202222212121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 121212222202221 - 2⁹ = 121212222201709 is a prime.

It is a super-2 number, since 2×121212222202221² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 121212222202191 and 121212222202200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121212262202221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20202037033701 + ... + 20202037033706.

It is an arithmetic number, because the mean of its divisors is an integer number (40404074067408).

Almost surely, 2^{121212222202221} is an apocalyptic number.

It is an amenable number.

121212222202221 is a deficient number, since it is larger than the sum of its proper divisors (40404074067411).

121212222202221 is an equidigital number, since it uses as much as digits as its factorization.

121212222202221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40404074067410.

The product of its (nonzero) digits is 1024, while the sum is 24.

Adding to 121212222202221 its reverse (122202222212121), we get a palindrome (243414444414342).

The spelling of 121212222202221 in words is "one hundred twenty-one trillion, two hundred twelve billion, two hundred twenty-two million, two hundred two thousand, two hundred twenty-one".