211012221491 has 2 divisors, whose sum is σ = 211012221492. Its totient is φ = 211012221490.

The previous prime is 211012221473. The next prime is 211012221503. The reversal of 211012221491 is 194122210112.

211012221491 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 is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211012221491 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 211012221491.

It is not a weakly prime, because it can be changed into another prime (211012221461) 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, 105506110745 + 105506110746.

It is an arithmetic number, because the mean of its divisors is an integer number (105506110746).

Almost surely, 2^211012221491 is an apocalyptic number.

211012221491 is a deficient number, since it is larger than the sum of its proper divisors (1).

211012221491 is an equidigital number, since it uses as much as digits as its factorization.

211012221491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 26.

The spelling of 211012221491 in words is "two hundred eleven billion, twelve million, two hundred twenty-one thousand, four hundred ninety-one".