21111212011049 has 2 divisors, whose sum is σ = 21111212011050. Its totient is φ = 21111212011048.

The previous prime is 21111212010979. The next prime is 21111212011051. The reversal of 21111212011049 is 94011021211112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19449484764649 + 1661727246400 = 4410157^2 + 1289080^2 .

It is a cyclic number.

It is not a de Polignac number, because 21111212011049 - 2⁴⁰ = 20011700383273 is a prime.

Together with 21111212011051, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21111212011649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555606005524 + 10555606005525.

It is an arithmetic number, because the mean of its divisors is an integer number (10555606005525).

Almost surely, 2^{21111212011049} is an apocalyptic number.

It is an amenable number.

21111212011049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111212011049 is an equidigital number, since it uses as much as digits as its factorization.

21111212011049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 26.

The spelling of 21111212011049 in words is "twenty-one trillion, one hundred eleven billion, two hundred twelve million, eleven thousand, forty-nine".