21211001102191 has 2 divisors, whose sum is σ = 21211001102192. Its totient is φ = 21211001102190.

The previous prime is 21211001102171. The next prime is 21211001102321. The reversal of 21211001102191 is 19120110011212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21211001102191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21211001102141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605500551095 + 10605500551096.

It is an arithmetic number, because the mean of its divisors is an integer number (10605500551096).

Almost surely, 2^{21211001102191} is an apocalyptic number.

21211001102191 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211001102191 is an equidigital number, since it uses as much as digits as its factorization.

21211001102191 is an evil number, because the sum of its binary digits is even.

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

The spelling of 21211001102191 in words is "twenty-one trillion, two hundred eleven billion, one million, one hundred two thousand, one hundred ninety-one".