121212212321 has 2 divisors, whose sum is σ = 121212212322. Its totient is φ = 121212212320.

The previous prime is 121212212287. The next prime is 121212212339. The reversal of 121212212321 is 123212212121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 82033552225 + 39178660096 = 286415^2 + 197936^2 .

It is an emirp because it is prime and its reverse (123212212121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121212212321 - 2⁶ = 121212212257 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121212212293 and 121212212302.

It is not a weakly prime, because it can be changed into another prime (121212218321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60606106160 + 60606106161.

It is an arithmetic number, because the mean of its divisors is an integer number (60606106161).

Almost surely, 2^121212212321 is an apocalyptic number.

It is an amenable number.

121212212321 is a deficient number, since it is larger than the sum of its proper divisors (1).

121212212321 is an equidigital number, since it uses as much as digits as its factorization.

121212212321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 192, while the sum is 20.

Adding to 121212212321 its reverse (123212212121), we get a palindrome (244424424442).

The spelling of 121212212321 in words is "one hundred twenty-one billion, two hundred twelve million, two hundred twelve thousand, three hundred twenty-one".