2165981667211 has 2 divisors, whose sum is σ = 2165981667212. Its totient is φ = 2165981667210.

The previous prime is 2165981667137. The next prime is 2165981667247. The reversal of 2165981667211 is 1127661895612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2165981667211 - 2¹¹ = 2165981665163 is a prime.

It is not a weakly prime, because it can be changed into another prime (2165981667911) 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, 1082990833605 + 1082990833606.

It is an arithmetic number, because the mean of its divisors is an integer number (1082990833606).

Almost surely, 2^{2165981667211} is an apocalyptic number.

2165981667211 is a deficient number, since it is larger than the sum of its proper divisors (1).

2165981667211 is an equidigital number, since it uses as much as digits as its factorization.

2165981667211 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2177280, while the sum is 55.

The spelling of 2165981667211 in words is "two trillion, one hundred sixty-five billion, nine hundred eighty-one million, six hundred sixty-seven thousand, two hundred eleven".