211665571489 has 2 divisors, whose sum is σ = 211665571490. Its totient is φ = 211665571488.

The previous prime is 211665571471. The next prime is 211665571549. The reversal of 211665571489 is 984175566112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 183340681489 + 28324890000 = 428183^2 + 168300^2 .

It is a cyclic number.

It is not a de Polignac number, because 211665571489 - 2¹¹ = 211665569441 is a prime.

It is not a weakly prime, because it can be changed into another prime (211665571409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105832785744 + 105832785745.

It is an arithmetic number, because the mean of its divisors is an integer number (105832785745).

Almost surely, 2^211665571489 is an apocalyptic number.

It is an amenable number.

211665571489 is a deficient number, since it is larger than the sum of its proper divisors (1).

211665571489 is an equidigital number, since it uses as much as digits as its factorization.

211665571489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3628800, while the sum is 55.

The spelling of 211665571489 in words is "two hundred eleven billion, six hundred sixty-five million, five hundred seventy-one thousand, four hundred eighty-nine".