121002200021 has 2 divisors, whose sum is σ = 121002200022. Its totient is φ = 121002200020.

The previous prime is 121002199999. The next prime is 121002200027. The reversal of 121002200021 is 120002200121.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 114010899025 + 6991300996 = 337655^2 + 83614^2 .

It is an emirp because it is prime and its reverse (120002200121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121002200021 - 2¹⁰ = 121002198997 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121002199975 and 121002200011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121002200027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60501100010 + 60501100011.

It is an arithmetic number, because the mean of its divisors is an integer number (60501100011).

Almost surely, 2^121002200021 is an apocalyptic number.

It is an amenable number.

121002200021 is a deficient number, since it is larger than the sum of its proper divisors (1).

121002200021 is an equidigital number, since it uses as much as digits as its factorization.

121002200021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 121002200021 its reverse (120002200121), we get a palindrome (241004400142).

The spelling of 121002200021 in words is "one hundred twenty-one billion, two million, two hundred thousand, twenty-one".