163999709 has 2 divisors, whose sum is σ = 163999710. Its totient is φ = 163999708.

The previous prime is 163999691. The next prime is 163999711. The reversal of 163999709 is 907999361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 163968025 + 31684 = 12805^2 + 178^2 .

It is an emirp because it is prime and its reverse (907999361) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-163999709 is a prime.

Together with 163999711, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (163999739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81999854 + 81999855.

It is an arithmetic number, because the mean of its divisors is an integer number (81999855).

Almost surely, 2^163999709 is an apocalyptic number.

It is an amenable number.

163999709 is a deficient number, since it is larger than the sum of its proper divisors (1).

163999709 is an equidigital number, since it uses as much as digits as its factorization.

163999709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 826686, while the sum is 53.

The square root of 163999709 is about 12806.2371132195. The cubic root of 163999709 is about 547.3700437301.

The spelling of 163999709 in words is "one hundred sixty-three million, nine hundred ninety-nine thousand, seven hundred nine".