121221002221 has 4 divisors (see below), whose sum is σ = 132241093344. Its totient is φ = 110200911100.

The previous prime is 121221002197. The next prime is 121221002261. The reversal of 121221002221 is 122200122121.

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 121221002221 - 2⁷ = 121221002093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121221002195 and 121221002204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221002261) 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, 5510045545 + ... + 5510045566.

It is an arithmetic number, because the mean of its divisors is an integer number (33060273336).

Almost surely, 2^121221002221 is an apocalyptic number.

121221002221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121221002221 is a deficient number, since it is larger than the sum of its proper divisors (11020091123).

121221002221 is a wasteful number, since it uses less digits than its factorization.

121221002221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11020091122.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 121221002221 its reverse (122200122121), we get a palindrome (243421124342).

The spelling of 121221002221 in words is "one hundred twenty-one billion, two hundred twenty-one million, two thousand, two hundred twenty-one".