199999966 has 16 divisors (see below), whose sum is σ = 323136000. Its totient is φ = 92532888.

The previous prime is 199999963. The next prime is 199999991. The reversal of 199999966 is 669999991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199999963) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59566 + ... + 62833.

It is an arithmetic number, because the mean of its divisors is an integer number (20196000).

Almost surely, 2^199999966 is an apocalyptic number.

199999966 is a deficient number, since it is larger than the sum of its proper divisors (123136034).

199999966 is a wasteful number, since it uses less digits than its factorization.

199999966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122463.

The product of its digits is 19131876, while the sum is 67.

The square root of 199999966 is about 14142.1344216494. The cubic root of 199999966 is about 584.8035145037.

It can be divided in two parts, 19999996 and 6, that added together give a palindrome (20000002).

The spelling of 199999966 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred sixty-six".