21199 has 8 divisors (see below), whose sum is σ = 23760. Its totient is φ = 18816.

The previous prime is 21193. The next prime is 21211. The reversal of 21199 is 99112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21199 - 2³ = 21191 is a prime.

It is a Duffinian number.

21199 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21191) 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, 472 + ... + 514.

It is an arithmetic number, because the mean of its divisors is an integer number (2970).

2²¹¹⁹⁹ is an apocalyptic number.

21199 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

21199 is a deficient number, since it is larger than the sum of its proper divisors (2561).

21199 is a wasteful number, since it uses less digits than its factorization.

21199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89.

The product of its digits is 162, while the sum is 22.

The square root of 21199 is about 145.5987637310. The cubic root of 21199 is about 27.6761149002.

The spelling of 21199 in words is "twenty-one thousand, one hundred ninety-nine".