199965019 has 2 divisors, whose sum is σ = 199965020. Its totient is φ = 199965018.

The previous prime is 199964993. The next prime is 199965023. The reversal of 199965019 is 910569991.

It is a strong prime.

It is an emirp because it is prime and its reverse (910569991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199965019 - 2¹⁵ = 199932251 is a prime.

It is a super-2 number, since 2×199965019² = 79972017647340722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (199965049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99982509 + 99982510.

It is an arithmetic number, because the mean of its divisors is an integer number (99982510).

Almost surely, 2^199965019 is an apocalyptic number.

199965019 is a deficient number, since it is larger than the sum of its proper divisors (1).

199965019 is an equidigital number, since it uses as much as digits as its factorization.

199965019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 196830, while the sum is 49.

The square root of 199965019 is about 14140.8988045315. The cubic root of 199965019 is about 584.7694506331.

The spelling of 199965019 in words is "one hundred ninety-nine million, nine hundred sixty-five thousand, nineteen".