211221002191 has 2 divisors, whose sum is σ = 211221002192. Its totient is φ = 211221002190.

The previous prime is 211221002177. The next prime is 211221002257. The reversal of 211221002191 is 191200122112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 211221002191 - 2⁷ = 211221002063 is a prime.

It is a super-2 number, since 2×211221002191² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211221002101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105610501095 + 105610501096.

It is an arithmetic number, because the mean of its divisors is an integer number (105610501096).

Almost surely, 2^211221002191 is an apocalyptic number.

211221002191 is a deficient number, since it is larger than the sum of its proper divisors (1).

211221002191 is an equidigital number, since it uses as much as digits as its factorization.

211221002191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 22.

The spelling of 211221002191 in words is "two hundred eleven billion, two hundred twenty-one million, two thousand, one hundred ninety-one".