199648321 has 2 divisors, whose sum is σ = 199648322. Its totient is φ = 199648320.

The previous prime is 199648301. The next prime is 199648327. The reversal of 199648321 is 123846991.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128482225 + 71166096 = 11335^2 + 8436^2 .

It is an emirp because it is prime and its reverse (123846991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199648321 - 2⁷ = 199648193 is a prime.

It is not a weakly prime, because it can be changed into another prime (199648327) 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, 99824160 + 99824161.

It is an arithmetic number, because the mean of its divisors is an integer number (99824161).

Almost surely, 2^199648321 is an apocalyptic number.

It is an amenable number.

199648321 is a deficient number, since it is larger than the sum of its proper divisors (1).

199648321 is an equidigital number, since it uses as much as digits as its factorization.

199648321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 43.

The square root of 199648321 is about 14129.6964227828. The cubic root of 199648321 is about 584.4605746586.

The spelling of 199648321 in words is "one hundred ninety-nine million, six hundred forty-eight thousand, three hundred twenty-one".