2121212122217 has 2 divisors, whose sum is σ = 2121212122218. Its totient is φ = 2121212122216.

The previous prime is 2121212122193. The next prime is 2121212122223. The reversal of 2121212122217 is 7122212121212.

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., 1522351274896 + 598860847321 = 1233836^2 + 773861^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121212122217 - 2²⁸ = 2120943686761 is a prime.

It is not a weakly prime, because it can be changed into another prime (2121212122297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060606061108 + 1060606061109.

It is an arithmetic number, because the mean of its divisors is an integer number (1060606061109).

Almost surely, 2^{2121212122217} is an apocalyptic number.

It is an amenable number.

2121212122217 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121212122217 is an equidigital number, since it uses as much as digits as its factorization.

2121212122217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 896, while the sum is 26.

Adding to 2121212122217 its reverse (7122212121212), we get a palindrome (9243424243429).

The spelling of 2121212122217 in words is "two trillion, one hundred twenty-one billion, two hundred twelve million, one hundred twenty-two thousand, two hundred seventeen".