2166071267449 has 2 divisors, whose sum is σ = 2166071267450. Its totient is φ = 2166071267448.

The previous prime is 2166071267447. The next prime is 2166071267471. The reversal of 2166071267449 is 9447621706612.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1974958030224 + 191113237225 = 1405332^2 + 437165^2 .

It is a cyclic number.

It is not a de Polignac number, because 2166071267449 - 2¹ = 2166071267447 is a prime.

Together with 2166071267447, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 2166071267449.

It is not a weakly prime, because it can be changed into another prime (2166071267447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1083035633724 + 1083035633725.

It is an arithmetic number, because the mean of its divisors is an integer number (1083035633725).

Almost surely, 2^{2166071267449} is an apocalyptic number.

It is an amenable number.

2166071267449 is a deficient number, since it is larger than the sum of its proper divisors (1).

2166071267449 is an equidigital number, since it uses as much as digits as its factorization.

2166071267449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6096384, while the sum is 55.

The spelling of 2166071267449 in words is "two trillion, one hundred sixty-six billion, seventy-one million, two hundred sixty-seven thousand, four hundred forty-nine".