199689 has 16 divisors (see below), whose sum is σ = 313728. Its totient is φ = 110592.

The previous prime is 199687. The next prime is 199697. The reversal of 199689 is 986991.

It is not a de Polignac number, because 199689 - 2¹ = 199687 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 199689.

It is not an unprimeable number, because it can be changed into a prime (199687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 649 + ... + 905.

It is an arithmetic number, because the mean of its divisors is an integer number (19608).

2¹⁹⁹⁶⁸⁹ is an apocalyptic number.

It is an amenable number.

199689 is a deficient number, since it is larger than the sum of its proper divisors (114039).

199689 is a wasteful number, since it uses less digits than its factorization.

199689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304.

The product of its digits is 34992, while the sum is 42.

The square root of 199689 is about 446.8657516526. The cubic root of 199689 is about 58.4500267216.

It can be divided in two parts, 199 and 689, that added together give a palindrome (888).

The spelling of 199689 in words is "one hundred ninety-nine thousand, six hundred eighty-nine".