211221023291 has 2 divisors, whose sum is σ = 211221023292. Its totient is φ = 211221023290.

The previous prime is 211221023239. The next prime is 211221023399. The reversal of 211221023291 is 192320122112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 211221023291 - 2¹⁴ = 211221006907 is a prime.

It is a super-2 number, since 2×211221023291² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 211221023291.

It is not a weakly prime, because it can be changed into another prime (211221023491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105610511645 + 105610511646.

It is an arithmetic number, because the mean of its divisors is an integer number (105610511646).

Almost surely, 2^211221023291 is an apocalyptic number.

211221023291 is a deficient number, since it is larger than the sum of its proper divisors (1).

211221023291 is an equidigital number, since it uses as much as digits as its factorization.

211221023291 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 26.

The spelling of 211221023291 in words is "two hundred eleven billion, two hundred twenty-one million, twenty-three thousand, two hundred ninety-one".