121111011209 has 2 divisors, whose sum is σ = 121111011210. Its totient is φ = 121111011208.

The previous prime is 121111011199. The next prime is 121111011251. The reversal of 121111011209 is 902110111121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107004223225 + 14106787984 = 327115^2 + 118772^2 .

It is an emirp because it is prime and its reverse (902110111121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121111011209 - 2¹⁶ = 121110945673 is a prime.

It is not a weakly prime, because it can be changed into another prime (121111011299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60555505604 + 60555505605.

It is an arithmetic number, because the mean of its divisors is an integer number (60555505605).

Almost surely, 2^121111011209 is an apocalyptic number.

It is an amenable number.

121111011209 is a deficient number, since it is larger than the sum of its proper divisors (1).

121111011209 is an equidigital number, since it uses as much as digits as its factorization.

121111011209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 20.

The spelling of 121111011209 in words is "one hundred twenty-one billion, one hundred eleven million, eleven thousand, two hundred nine".