2164991 has 2 divisors, whose sum is σ = 2164992. Its totient is φ = 2164990.

The previous prime is 2164979. The next prime is 2165017. The reversal of 2164991 is 1994612.

2164991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2164991 - 2⁶ = 2164927 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2164901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1082495 + 1082496.

It is an arithmetic number, because the mean of its divisors is an integer number (1082496).

2^2164991 is an apocalyptic number.

2164991 is a deficient number, since it is larger than the sum of its proper divisors (1).

2164991 is an equidigital number, since it uses as much as digits as its factorization.

2164991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3888, while the sum is 32.

The square root of 2164991 is about 1471.3908386285. The cubic root of 2164991 is about 129.3655676259.

The spelling of 2164991 in words is "two million, one hundred sixty-four thousand, nine hundred ninety-one".