21220111001191 has 2 divisors, whose sum is σ = 21220111001192. Its totient is φ = 21220111001190.

The previous prime is 21220111001099. The next prime is 21220111001267. The reversal of 21220111001191 is 19110011102212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21220111001191 - 2²⁵ = 21220077446759 is a prime.

It is a super-2 number, since 2×21220111001191² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21220111007191) 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, 10610055500595 + 10610055500596.

It is an arithmetic number, because the mean of its divisors is an integer number (10610055500596).

Almost surely, 2^{21220111001191} is an apocalyptic number.

21220111001191 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220111001191 is an equidigital number, since it uses as much as digits as its factorization.

21220111001191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 22.

The spelling of 21220111001191 in words is "twenty-one trillion, two hundred twenty billion, one hundred eleven million, one thousand, one hundred ninety-one".