2165994247 has 2 divisors, whose sum is σ = 2165994248. Its totient is φ = 2165994246.

The previous prime is 2165994241. The next prime is 2165994251. The reversal of 2165994247 is 7424995612.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2165994247 - 2⁷ = 2165994119 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2165994247.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2165994241) 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, 1082997123 + 1082997124.

It is an arithmetic number, because the mean of its divisors is an integer number (1082997124).

Almost surely, 2^2165994247 is an apocalyptic number.

2165994247 is a deficient number, since it is larger than the sum of its proper divisors (1).

2165994247 is an equidigital number, since it uses as much as digits as its factorization.

2165994247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1088640, while the sum is 49.

The square root of 2165994247 is about 46540.2433061968. The cubic root of 2165994247 is about 1293.8554701229.

The spelling of 2165994247 in words is "two billion, one hundred sixty-five million, nine hundred ninety-four thousand, two hundred forty-seven".