2165981671331 has 2 divisors, whose sum is σ = 2165981671332. Its totient is φ = 2165981671330.

The previous prime is 2165981671277. The next prime is 2165981671351. The reversal of 2165981671331 is 1331761895612.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2165981671331 is a prime.

It is a super-2 number, since 2×2165981671331² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2165981671351) 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, 1082990835665 + 1082990835666.

It is an arithmetic number, because the mean of its divisors is an integer number (1082990835666).

Almost surely, 2^{2165981671331} is an apocalyptic number.

2165981671331 is a deficient number, since it is larger than the sum of its proper divisors (1).

2165981671331 is an equidigital number, since it uses as much as digits as its factorization.

2165981671331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1632960, while the sum is 53.

The spelling of 2165981671331 in words is "two trillion, one hundred sixty-five billion, nine hundred eighty-one million, six hundred seventy-one thousand, three hundred thirty-one".