12121354321 has 2 divisors, whose sum is σ = 12121354322. Its totient is φ = 12121354320.

The previous prime is 12121354319. The next prime is 12121354363. The reversal of 12121354321 is 12345312121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10609000000 + 1512354321 = 103000^2 + 38889^2 .

It is an emirp because it is prime and its reverse (12345312121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12121354321 - 2¹ = 12121354319 is a prime.

Together with 12121354319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (12121354391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6060677160 + 6060677161.

It is an arithmetic number, because the mean of its divisors is an integer number (6060677161).

Almost surely, 2^12121354321 is an apocalyptic number.

It is an amenable number.

12121354321 is a deficient number, since it is larger than the sum of its proper divisors (1).

12121354321 is an equidigital number, since it uses as much as digits as its factorization.

12121354321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 25.

Adding to 12121354321 its reverse (12345312121), we get a palindrome (24466666442).

The spelling of 12121354321 in words is "twelve billion, one hundred twenty-one million, three hundred fifty-four thousand, three hundred twenty-one".