20199 has 4 divisors (see below), whose sum is σ = 26936. Its totient is φ = 13464.

The previous prime is 20183. The next prime is 20201. The reversal of 20199 is 99102.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20199 - 2⁴ = 20183 is a prime.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is a nialpdrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3364 + ... + 3369.

It is an arithmetic number, because the mean of its divisors is an integer number (6734).

2²⁰¹⁹⁹ is an apocalyptic number.

20199 is a deficient number, since it is larger than the sum of its proper divisors (6737).

20199 is an equidigital number, since it uses as much as digits as its factorization.

20199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6736.

The product of its (nonzero) digits is 162, while the sum is 21.

The square root of 20199 is about 142.1231860043. The cubic root of 20199 is about 27.2339073964.

It can be divided in two parts, 201 and 99, that added together give a triangular number (300 = T₂₄).

The spelling of 20199 in words is "twenty thousand, one hundred ninety-nine".