121111111210211 has 2 divisors, whose sum is σ = 121111111210212. Its totient is φ = 121111111210210.

The previous prime is 121111111210189. The next prime is 121111111210253. The reversal of 121111111210211 is 112012111111121.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121111111210211 - 2¹⁸ = 121111110948067 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121111111210211.

It is not a weakly prime, because it can be changed into another prime (121111111216211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60555555605105 + 60555555605106.

It is an arithmetic number, because the mean of its divisors is an integer number (60555555605106).

Almost surely, 2^{121111111210211} is an apocalyptic number.

121111111210211 is a deficient number, since it is larger than the sum of its proper divisors (1).

121111111210211 is an equidigital number, since it uses as much as digits as its factorization.

121111111210211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 17.

Adding to 121111111210211 its reverse (112012111111121), we get a palindrome (233123222321332).

The spelling of 121111111210211 in words is "one hundred twenty-one trillion, one hundred eleven billion, one hundred eleven million, two hundred ten thousand, two hundred eleven".