163888321 has 2 divisors, whose sum is σ = 163888322. Its totient is φ = 163888320.

The previous prime is 163888267. The next prime is 163888331. The reversal of 163888321 is 123888361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 114383025 + 49505296 = 10695^2 + 7036^2 .

It is an emirp because it is prime and its reverse (123888361) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-163888321 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (163888331) 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, 81944160 + 81944161.

It is an arithmetic number, because the mean of its divisors is an integer number (81944161).

Almost surely, 2^163888321 is an apocalyptic number.

It is an amenable number.

163888321 is a deficient number, since it is larger than the sum of its proper divisors (1).

163888321 is an equidigital number, since it uses as much as digits as its factorization.

163888321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 55296, while the sum is 40.

The square root of 163888321 is about 12801.8873999110. The cubic root of 163888321 is about 547.2460917555.

Adding to 163888321 its sum of digits (40), we get a palindrome (163888361).

The spelling of 163888321 in words is "one hundred sixty-three million, eight hundred eighty-eight thousand, three hundred twenty-one".