21083 has 4 divisors (see below), whose sum is σ = 21840. Its totient is φ = 20328.

The previous prime is 21067. The next prime is 21089. The reversal of 21083 is 38012.

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

It is a cyclic number.

It is not a de Polignac number, because 21083 - 2⁴ = 21067 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21089) 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, 335 + ... + 392.

It is an arithmetic number, because the mean of its divisors is an integer number (5460).

2²¹⁰⁸³ is an apocalyptic number.

21083 is a deficient number, since it is larger than the sum of its proper divisors (757).

21083 is an equidigital number, since it uses as much as digits as its factorization.

21083 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 756.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21083 is about 145.1998622589. The cubic root of 21083 is about 27.6255417132.

Adding to 21083 its reverse (38012), we get a palindrome (59095).

The spelling of 21083 in words is "twenty-one thousand, eighty-three".