121111212281 has 2 divisors, whose sum is σ = 121111212282. Its totient is φ = 121111212280.

The previous prime is 121111212197. The next prime is 121111212293. The reversal of 121111212281 is 182212111121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71337602281 + 49773610000 = 267091^2 + 223100^2 .

It is a cyclic number.

It is not a de Polignac number, because 121111212281 - 2¹⁰ = 121111211257 is a prime.

It is a super-2 number, since 2×121111212281² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (121111212581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60555606140 + 60555606141.

It is an arithmetic number, because the mean of its divisors is an integer number (60555606141).

Almost surely, 2^121111212281 is an apocalyptic number.

It is an amenable number.

121111212281 is a deficient number, since it is larger than the sum of its proper divisors (1).

121111212281 is an equidigital number, since it uses as much as digits as its factorization.

121111212281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 128, while the sum is 23.

The spelling of 121111212281 in words is "one hundred twenty-one billion, one hundred eleven million, two hundred twelve thousand, two hundred eighty-one".