211121121961 has 2 divisors, whose sum is σ = 211121121962. Its totient is φ = 211121121960.

The previous prime is 211121121947. The next prime is 211121121971. The reversal of 211121121961 is 169121121112.

211121121961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 122104819225 + 89016302736 = 349435^2 + 298356^2 .

It is a cyclic number.

It is not a de Polignac number, because 211121121961 - 2¹⁹ = 211120597673 is a prime.

It is not a weakly prime, because it can be changed into another prime (211121121971) 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, 105560560980 + 105560560981.

It is an arithmetic number, because the mean of its divisors is an integer number (105560560981).

Almost surely, 2^211121121961 is an apocalyptic number.

It is an amenable number.

211121121961 is a deficient number, since it is larger than the sum of its proper divisors (1).

211121121961 is an equidigital number, since it uses as much as digits as its factorization.

211121121961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 28.

The spelling of 211121121961 in words is "two hundred eleven billion, one hundred twenty-one million, one hundred twenty-one thousand, nine hundred sixty-one".