11211021961 has 2 divisors, whose sum is σ = 11211021962. Its totient is φ = 11211021960.

The previous prime is 11211021959. The next prime is 11211022003. The reversal of 11211021961 is 16912011211.

11211021961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11210574400 + 447561 = 105880^2 + 669^2 .

It is a cyclic number.

It is not a de Polignac number, because 11211021961 - 2¹ = 11211021959 is a prime.

Together with 11211021959, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (11211021911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5605510980 + 5605510981.

It is an arithmetic number, because the mean of its divisors is an integer number (5605510981).

Almost surely, 2^11211021961 is an apocalyptic number.

It is an amenable number.

11211021961 is a deficient number, since it is larger than the sum of its proper divisors (1).

11211021961 is an equidigital number, since it uses as much as digits as its factorization.

11211021961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 25.

The spelling of 11211021961 in words is "eleven billion, two hundred eleven million, twenty-one thousand, nine hundred sixty-one".