121211202221 has 4 divisors (see below), whose sum is σ = 127590739200. Its totient is φ = 114831665244.

The previous prime is 121211202197. The next prime is 121211202227. The reversal of 121211202221 is 122202112121.

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 121211202221 - 2³⁴ = 104031333037 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121211202221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121211202227) 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, 3189768461 + ... + 3189768498.

It is an arithmetic number, because the mean of its divisors is an integer number (31897684800).

Almost surely, 2^121211202221 is an apocalyptic number.

It is an amenable number.

121211202221 is a deficient number, since it is larger than the sum of its proper divisors (6379536979).

121211202221 is an equidigital number, since it uses as much as digits as its factorization.

121211202221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6379536978.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 121211202221 its reverse (122202112121), we get a palindrome (243413314342).

The spelling of 121211202221 in words is "one hundred twenty-one billion, two hundred eleven million, two hundred two thousand, two hundred twenty-one".