199966865 has 16 divisors (see below), whose sum is σ = 274613760. Its totient is φ = 136933440.

The previous prime is 199966859. The next prime is 199966873. The reversal of 199966865 is 568669991.

It is a de Polignac number, because none of the positive numbers 2^k-199966865 is a prime.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 25256 + ... + 32214.

It is an arithmetic number, because the mean of its divisors is an integer number (17163360).

Almost surely, 2^199966865 is an apocalyptic number.

It is an amenable number.

199966865 is a deficient number, since it is larger than the sum of its proper divisors (74646895).

199966865 is an equidigital number, since it uses as much as digits as its factorization.

199966865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7792.

The product of its digits is 6298560, while the sum is 59.

The square root of 199966865 is about 14140.9640760452. The cubic root of 199966865 is about 584.7712500830.

The spelling of 199966865 in words is "one hundred ninety-nine million, nine hundred sixty-six thousand, eight hundred sixty-five".